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• MYSQL UPDATE with IN and Subquery

  - by Johal

  Hi i have tables like this : table entry : id | total_comments ___________ 1 | 0 2 | 0 3 | 0 4 | 0 table comments : id | eid | comment ___________ 1 | 1 | comment sdfd 2 | 1 | testing testing 3 | 1 | comment text 4 | 2 | dummy comment 5 | 2 | sample comment 6 | 1 | fg fgh dfh Query i write : UPDATE entry SET total_comments = total_comments + 1 WHERE id IN ( SELECT eid FROM comments WHERE id IN (1,2,3,4,5,6)) Results i get is : table entry : id | total_comments ___________ 1 | 1 2 | 1 3 | 0 4 | 0 Expected results : table entry : id | total_comments ___________ 1 | 4 2 | 2 3 | 0 4 | 0 Any help will be appreciated.

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• How to differentiate two tables

  - by Nemat

  I have two tables and I want to get all records from one table that are different from the records in second table. Eg.: if we have four records in the first table like A,B,C,D and three records in the second table thats A,B,C then the answer of query should be D. I have tried "EXCEPT" operator but it doesn't work fine. Kindly help me in writing correct query for the given problem.

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• Copy (or USE) data from two tables in different databases

  - by Z77

  I don-t know how to use one table from one database and second table from another databse at the same time or copy data from table in one database to table from another databse. I tried following query: select * into NewTable from existingdb.dbo.existingTable; But it doesnt't work.

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• filling a form with parameter already selected using ajax

  - by kawtousse

  hi every one, My goal untill now is to fill a form with values from a table (html table). it is a kind of refreshing the form. so the user who wants to modify the html table through the form must prefill the form with values wich he already selected. I used the DOM to acces to each row and cell in the table and i used ajax to pass parameter to other jsp. but Iam confused what shall be the next step to fill the form.

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• How to pass the parameter to the function

  - by avaro

  Hi, I have stored procedure that takes input parameter of table type. procedure test( name samptable type); My table has the structure like table: samptable( name chracter varying; address text[]; ) So how shoul i pass the values to the function to fill the table.

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• How to submit the correct div elements (not the div that's hidden)?

  - by user356651

  Hello, I have the following code working fine but the problem is that it always submits the first div (article) even though it's hidden. My question is how do I submit the form and the elements in the form in the div that's shown? (if I select Music radiobutton, I want to submit the input elements of the Music Div not the Article div. Thanks. $(document).ready(function(){ $("input[name$='itemlist']").click(function() { var selection = $(this).val(); $("div.box").hide(); $("#"+selection).show(); }); }); <!--radio buttons--> <div id="articleselection"><input name="itemlist" type="radio" value="article" /> Article/Book </div> <div id="musicselection"><input name="itemlist" type="radio" value="music" /> Music</div> <!--article div starts--> <div id="article" class="box"> <table class="fieldgroup"> <tr><td>Journal Title: <input id="JournalTitle" name="JournalTitle" type="text" size="60" class="f-name" tabindex="1" value="JournalTitle"> </table> <table class="fieldgroup"> <tr><td>Article Author: <input id="ArticleAuthor" name="ArticleAuthor" type="text" size="40" class="f-name" tabindex="2" value="<"ArticleAuthor"></td></tr> </table> </div> <!--music div starts--> <div id="music" class="box"> <table class="fieldgroup"> <tr><td>Music Title: <input id="Music Title" name="Music Title" type="text" size="60" class="f-name" tabindex="1" value="Music Title"> </table> <table class="fieldgroup"> <tr><td> Music Author: <input id="MusicAuthor" name="Music Author" type="text" size="40" class="f-name" tabindex="2" value="<"MusicAuthor"></td></tr> </table> </div>

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• Create trigger for auto incerment id and default unix datetime

  - by user1804985

  Any one help me to create a trigger for auto increment fld_id and Unix datetime. My table field is fld_id(int),fld_date(number),fld_value(varchar2). My insert query is insert into table (fld_value)values('xxx'); insert into table (fld_value)values('yyy'); I need the table record like this fld_id fld_date fld_value 1 1354357476 xxx 2 1354357478 yyy Please help me to create this.I can't able to do this..

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• Bulk Update in MYSQl

  - by user351806

  I have a site which has client side and admin side. There is a table called account History. which contains fields like uid | accountBalance | PaymentStatus | Date. Now this table has to be updated every month for all the paid users and the table is bulk. So what is the best way to update the table every month.Do i need to select all the uid's and update.

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• The SSIS tuning tip that everyone misses

  - by Rob Farley

  I know that everyone misses this, because I’m yet to find someone who doesn’t have a bit of an epiphany when I describe this. When tuning Data Flows in SQL Server Integration Services, people see the Data Flow as moving from the Source to the Destination, passing through a number of transformations. What people don’t consider is the Source, getting the data out of a database. Remember, the source of data for your Data Flow is not your Source Component. It’s wherever the data is, within your database, probably on a disk somewhere. You need to tune your query to optimise it for SSIS, and this is what most people fail to do. I’m not suggesting that people don’t tune their queries – there’s plenty of information out there about making sure that your queries run as fast as possible. But for SSIS, it’s not about how fast your query runs. Let me say that again, but in bolder text: The speed of an SSIS Source is not about how fast your query runs. If your query is used in a Source component for SSIS, the thing that matters is how fast it starts returning data. In particular, those first 10,000 rows to populate that first buffer, ready to pass down the rest of the transformations on its way to the Destination. Let’s look at a very simple query as an example, using the AdventureWorks database: We’re picking the different Weight values out of the Product table, and it’s doing this by scanning the table and doing a Sort. It’s a Distinct Sort, which means that the duplicates are discarded. It'll be no surprise to see that the data produced is sorted. Obvious, I know, but I'm making a comparison to what I'll do later. Before I explain the problem here, let me jump back into the SSIS world... If you’ve investigated how to tune an SSIS flow, then you’ll know that some SSIS Data Flow Transformations are known to be Blocking, some are Partially Blocking, and some are simply Row transformations. Take the SSIS Sort transformation, for example. I’m using a larger data set for this, because my small list of Weights won’t demonstrate it well enough. Seven buffers of data came out of the source, but none of them could be pushed past the Sort operator, just in case the last buffer contained the data that would be sorted into the first buffer. This is a blocking operation. Back in the land of T-SQL, we consider our Distinct Sort operator. It’s also blocking. It won’t let data through until it’s seen all of it. If you weren’t okay with blocking operations in SSIS, why would you be happy with them in an execution plan? The source of your data is not your OLE DB Source. Remember this. The source of your data is the NCIX/CIX/Heap from which it’s being pulled. Picture it like this... the data flowing from the Clustered Index, through the Distinct Sort operator, into the SELECT operator, where a series of SSIS Buffers are populated, flowing (as they get full) down through the SSIS transformations. Alright, I know that I’m taking some liberties here, because the two queries aren’t the same, but consider the visual. The data is flowing from your disk and through your execution plan before it reaches SSIS, so you could easily find that a blocking operation in your plan is just as painful as a blocking operation in your SSIS Data Flow. Luckily, T-SQL gives us a brilliant query hint to help avoid this. OPTION (FAST 10000) This hint means that it will choose a query which will optimise for the first 10,000 rows – the default SSIS buffer size. And the effect can be quite significant. First let’s consider a simple example, then we’ll look at a larger one. Consider our weights. We don’t have 10,000, so I’m going to use OPTION (FAST 1) instead. You’ll notice that the query is more expensive, using a Flow Distinct operator instead of the Distinct Sort. This operator is consuming 84% of the query, instead of the 59% we saw from the Distinct Sort. But the first row could be returned quicker – a Flow Distinct operator is non-blocking. The data here isn’t sorted, of course. It’s in the same order that it came out of the index, just with duplicates removed. As soon as a Flow Distinct sees a value that it hasn’t come across before, it pushes it out to the operator on its left. It still has to maintain the list of what it’s seen so far, but by handling it one row at a time, it can push rows through quicker. Overall, it’s a lot more work than the Distinct Sort, but if the priority is the first few rows, then perhaps that’s exactly what we want. The Query Optimizer seems to do this by optimising the query as if there were only one row coming through: This 1 row estimation is caused by the Query Optimizer imagining the SELECT operation saying “Give me one row” first, and this message being passed all the way along. The request might not make it all the way back to the source, but in my simple example, it does. I hope this simple example has helped you understand the significance of the blocking operator. Now I’m going to show you an example on a much larger data set. This data was fetching about 780,000 rows, and these are the Estimated Plans. The data needed to be Sorted, to support further SSIS operations that needed that. First, without the hint. ...and now with OPTION (FAST 10000): A very different plan, I’m sure you’ll agree. In case you’re curious, those arrows in the top one are 780,000 rows in size. In the second, they’re estimated to be 10,000, although the Actual figures end up being 780,000. The top one definitely runs faster. It finished several times faster than the second one. With the amount of data being considered, these numbers were in minutes. Look at the second one – it’s doing Nested Loops, across 780,000 rows! That’s not generally recommended at all. That’s “Go and make yourself a coffee” time. In this case, it was about six or seven minutes. The faster one finished in about a minute. But in SSIS-land, things are different. The particular data flow that was consuming this data was significant. It was being pumped into a Script Component to process each row based on previous rows, creating about a dozen different flows. The data flow would take roughly ten minutes to run – ten minutes from when the data first appeared. The query that completes faster – chosen by the Query Optimizer with no hints, based on accurate statistics (rather than pretending the numbers are smaller) – would take a minute to start getting the data into SSIS, at which point the ten-minute flow would start, taking eleven minutes to complete. The query that took longer – chosen by the Query Optimizer pretending it only wanted the first 10,000 rows – would take only ten seconds to fill the first buffer. Despite the fact that it might have taken the database another six or seven minutes to get the data out, SSIS didn’t care. Every time it wanted the next buffer of data, it was already available, and the whole process finished in about ten minutes and ten seconds. When debugging SSIS, you run the package, and sit there waiting to see the Debug information start appearing. You look for the numbers on the data flow, and seeing operators going Yellow and Green. Without the hint, I’d sit there for a minute. With the hint, just ten seconds. You can imagine which one I preferred. By adding this hint, it felt like a magic wand had been waved across the query, to make it run several times faster. It wasn’t the case at all – but it felt like it to SSIS.

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• Grandparent – Parent – Child Reports in SQL Developer

  - by thatjeffsmith

  You’ll never see one of these family stickers on my car, but I promise not to judge…much. Parent – Child reports are pretty straightforward in Oracle SQL Developer. You have a ‘parent’ report, and then one or more ‘child’ reports which are based off of a value in a selected row or value from the parent. If you need a quick tutorial to get up to speed on the subject, go ahead and take 5 minutes Shortly before I left for vacation 2 weeks agao, I got an interesting question from one of my Twitter Followers: @thatjeffsmith any luck with the #Oracle awr reports in #SQLDeveloper?This is easy with multi generation parent>child Done in #dbvisualizer — Ronald Rood (@Ik_zelf) August 26, 2012 Now that I’m back from vacation, I can tell Ronald and everyone else that the answer is ‘Yes!’ And here’s how Time to Get Out Your XML Editor Don’t have one? That’s OK, SQL Developer can edit XML files. While the Reporting interface doesn’t surface the ability to create multi-generational reports, the underlying code definitely supports it. We just need to hack away at the XML that powers a report. For this example I’m going to start simple. A query that brings back DEPARTMENTs, then EMPLOYEES, then JOBs. We can build the first two parts of the report using the report editor. A Parent-Child report in Oracle SQL Developer (Departments – Employees) Save the Report to XML Once you’ve generated the XML file, open it with your favorite XML editor. For this example I’ll be using the build-it XML editor in SQL Developer. SQL Developer Reports in their raw XML glory! Right after the PDF element in the XML document, we can start a new ‘child’ report by inserting a DISPLAY element. I just copied and pasted the existing ‘display’ down so I wouldn’t have to worry about screwing anything up. Note I also needed to change the ‘master’ name so it wouldn’t confuse SQL Developer when I try to import/open a report that has the same name. Also I needed to update the binds tags to reflect the names from the child versus the original parent report. This is pretty easy to figure out on your own actually – I mean I’m no real developer and I got it pretty quick. <?xml version="1.0" encoding="UTF-8" ?> <displays> <display id="92857fce-0139-1000-8006-7f0000015340" type="" style="Table" enable="true"> <name><![CDATA[Grandparent]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[select * from hr.departments]]></sql> </query> <pdf version="VERSION_1_7" compression="CONTENT"> <docproperty title="" author="" subject="" keywords="" /> <cell toppadding="2" bottompadding="2" leftpadding="2" rightpadding="2" horizontalalign="LEFT" verticalalign="TOP" wrap="true" /> <column> <heading font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="FIRST_PAGE" /> <footing font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="NONE" /> <blob blob="NONE" zip="false" /> </column> <table font="Courier" size="10" style="NORMAL" color="-16777216" userowshading="false" oddrowshading="-1" evenrowshading="-1" showborders="true" spacingbefore="12" spacingafter="12" horizontalalign="LEFT" /> <header enable="false" generatedate="false"> <data> null </data> </header> <footer enable="false" generatedate="false"> <data value="null" /> </footer> <security enable="false" useopenpassword="false" openpassword="" encryption="EXCLUDE_METADATA"> <permission enable="false" permissionpassword="" allowcopying="true" allowprinting="true" allowupdating="false" allowaccessdevices="true" /> </security> <pagesetup papersize="LETTER" orientation="1" measurement="in" margintop="1.0" marginbottom="1.0" marginleft="1.0" marginright="1.0" /> </pdf> <display id="null" type="" style="Table" enable="true"> <name><![CDATA[Parent]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[select * from hr.employees where department_id = EPARTMENT_ID]]></sql> <binds> <bind id="DEPARTMENT_ID"> <prompt><![CDATA[DEPARTMENT_ID]]></prompt> <tooltip><![CDATA[DEPARTMENT_ID]]></tooltip> <value><![CDATA[NULL_VALUE]]></value> </bind> </binds> </query> <pdf version="VERSION_1_7" compression="CONTENT"> <docproperty title="" author="" subject="" keywords="" /> <cell toppadding="2" bottompadding="2" leftpadding="2" rightpadding="2" horizontalalign="LEFT" verticalalign="TOP" wrap="true" /> <column> <heading font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="FIRST_PAGE" /> <footing font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="NONE" /> <blob blob="NONE" zip="false" /> </column> <table font="Courier" size="10" style="NORMAL" color="-16777216" userowshading="false" oddrowshading="-1" evenrowshading="-1" showborders="true" spacingbefore="12" spacingafter="12" horizontalalign="LEFT" /> <header enable="false" generatedate="false"> <data> null </data> </header> <footer enable="false" generatedate="false"> <data value="null" /> </footer> <security enable="false" useopenpassword="false" openpassword="" encryption="EXCLUDE_METADATA"> <permission enable="false" permissionpassword="" allowcopying="true" allowprinting="true" allowupdating="false" allowaccessdevices="true" /> </security> <pagesetup papersize="LETTER" orientation="1" measurement="in" margintop="1.0" marginbottom="1.0" marginleft="1.0" marginright="1.0" /> </pdf> <display id="null" type="" style="Table" enable="true"> <name><![CDATA[Child]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[select * from hr.jobs where job_id = :JOB_ID]]></sql> <binds> <bind id="JOB_ID"> <prompt><![CDATA[JOB_ID]]></prompt> <tooltip><![CDATA[JOB_ID]]></tooltip> <value><![CDATA[NULL_VALUE]]></value> </bind> </binds> </query> <pdf version="VERSION_1_7" compression="CONTENT"> <docproperty title="" author="" subject="" keywords="" /> <cell toppadding="2" bottompadding="2" leftpadding="2" rightpadding="2" horizontalalign="LEFT" verticalalign="TOP" wrap="true" /> <column> <heading font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="FIRST_PAGE" /> <footing font="Courier" size="10" style="NORMAL" color="-16777216" rowshading="-1" labeling="NONE" /> <blob blob="NONE" zip="false" /> </column> <table font="Courier" size="10" style="NORMAL" color="-16777216" userowshading="false" oddrowshading="-1" evenrowshading="-1" showborders="true" spacingbefore="12" spacingafter="12" horizontalalign="LEFT" /> <header enable="false" generatedate="false"> <data> null </data> </header> <footer enable="false" generatedate="false"> <data value="null" /> </footer> <security enable="false" useopenpassword="false" openpassword="" encryption="EXCLUDE_METADATA"> <permission enable="false" permissionpassword="" allowcopying="true" allowprinting="true" allowupdating="false" allowaccessdevices="true" /> </security> <pagesetup papersize="LETTER" orientation="1" measurement="in" margintop="1.0" marginbottom="1.0" marginleft="1.0" marginright="1.0" /> </pdf> </display> </display> </display> </displays> Save the file and ‘Open Report…’ You’ll see your new report name in the tree. You just need to double-click it to open it. Here’s what it looks like running A 3 generation family Now Let’s Build an AWR Text Report Ronald wanted to have the ability to query AWR snapshots and generate the AWR reports. That requires a few inputs, including a START and STOP snapshot ID. That basically tells AWR what time period to use for generating the report. And here’s where it gets tricky. We’ll need to use aliases for the SNAP_ID column. Since we’re using the same column name from 2 different queries, we need to use different bind variables. Fortunately for us, SQL Developer’s clever enough to use the column alias as the BIND. Here’s what I mean: Grandparent Query SELECT snap_id start1, begin_interval_time, end_interval_time FROM dba_hist_snapshot ORDER BY 1 asc Parent Query SELECT snap_id stop1, begin_interval_time, end_interval_time, :START1 carry FROM dba_hist_snapshot WHERE snap_id > :START1 ORDER BY 1 asc And here’s where it gets even trickier – you can’t reference a bind from outside the parent query. My grandchild report can’t reference a value from the grandparent report. So I just carry the selected value down to the parent. In my parent query SELECT you see the ‘:START1′ at the end? That’s making that value available to me when I use it in my grandchild query. To complicate things a bit further, I can’t have a column name with a ‘:’ in it, or SQL Developer will get confused when I try to reference the value of the variable with the ‘:’ – and ‘::Name’ doesn’t work. But that’s OK, just alias it. Grandchild Query Select Output From Table(Dbms_Workload_Repository.Awr_Report_Text(1298953802, 1,:CARRY, :STOP1)); Ok, and the last trick – I hard-coded my report to use my database’s DB_ID and INST_ID into the AWR package call. Now a smart person could figure out a way to make that work on any database, but I got lazy and and ran out of time. But this should be far enough for you to take it from here. Here’s what my report looks like now: Caution: don’t run this if you haven’t licensed Enterprise Edition with Diagnostic Pack. The Raw XML for this AWR Report <?xml version="1.0" encoding="UTF-8" ?> <displays> <display id="927ba96c-0139-1000-8001-7f0000015340" type="" style="Table" enable="true"> <name><![CDATA[AWR Start Stop Report Final]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[SELECT snap_id start1, begin_interval_time, end_interval_time FROM dba_hist_snapshot ORDER BY 1 asc]]></sql> </query> <display id="null" type="" style="Table" enable="true"> <name><![CDATA[Stop SNAP_ID]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[SELECT snap_id stop1, begin_interval_time, end_interval_time, :START1 carry FROM dba_hist_snapshot WHERE snap_id > :START1 ORDER BY 1 asc]]></sql> </query> <display id="null" type="" style="Table" enable="true"> <name><![CDATA[AWR Report]]></name> <description><![CDATA[]]></description> <tooltip><![CDATA[]]></tooltip> <drillclass><![CDATA[null]]></drillclass> <CustomValues> <TYPE>horizontal</TYPE> </CustomValues> <query> <sql><![CDATA[Select Output From Table(Dbms_Workload_Repository.Awr_Report_Text(1298953802, 1,:CARRY, :STOP1 ))]]></sql> </query> </display> </display> </display> </displays> Should We Build Support for Multiple Levels of Reports into the User Interface? Let us know! A comment here or a suggestion on our SQL Developer Exchange might help your case!

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• help with fixing fwts errors log

  - by jasmines

  Here is an extract of results.log: MTRR validation. Test 1 of 3: Validate the kernel MTRR IOMEM setup. FAILED [MEDIUM] MTRRIncorrectAttr: Test 1, Memory range 0xc0000000 to 0xdfffffff (PCI Bus 0000:00) has incorrect attribute Write-Combining. FAILED [MEDIUM] MTRRIncorrectAttr: Test 1, Memory range 0xfee01000 to 0xffffffff (PCI Bus 0000:00) has incorrect attribute Write-Protect. ==================================================================================================== Test 1 of 1: Kernel log error check. Kernel message: [ 0.208079] [Firmware Bug]: ACPI: BIOS _OSI(Linux) query ignored ADVICE: This is not exactly a failure mode but a warning from the kernel. The _OSI() method has implemented a match to the 'Linux' query in the DSDT and this is redundant because the ACPI driver matches onto the Windows _OSI strings by default. FAILED [HIGH] KlogACPIErrorMethodExecutionParse: Test 1, HIGH Kernel message: [ 3.512783] ACPI Error : Method parse/execution failed [\_SB_.PCI0.GFX0._DOD] (Node f7425858), AE_AML_PACKAGE_LIMIT (20110623/psparse-536) ADVICE: This is a bug picked up by the kernel, but as yet, the firmware test suite has no diagnostic advice for this particular problem. Found 1 unique errors in kernel log. ==================================================================================================== Check if system is using latest microcode. ---------------------------------------------------------------------------------------------------- Cannot read microcode file /usr/share/misc/intel-microcode.dat. Aborted test, initialisation failed. ==================================================================================================== MSR register tests. FAILED [MEDIUM] MSRCPUsInconsistent: Test 1, MSR SYSENTER_ESP (0x175) has 1 inconsistent values across 2 CPUs for (shift: 0 mask: 0xffffffffffffffff). MSR CPU 0 -> 0xf7bb9c40 vs CPU 1 -> 0xf7bc7c40 FAILED [MEDIUM] MSRCPUsInconsistent: Test 1, MSR MISC_ENABLE (0x1a0) has 1 inconsistent values across 2 CPUs for (shift: 0 mask: 0x400c51889). MSR CPU 0 -> 0x850088 vs CPU 1 -> 0x850089 ==================================================================================================== Checks firmware has set PCI Express MaxReadReq to a higher value on non-motherboard devices. ---------------------------------------------------------------------------------------------------- Test 1 of 1: Check firmware settings MaxReadReq for PCI Express devices. MaxReadReq for pci://00:00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 03) is low (128) [Audio device]. MaxReadReq for pci://00:02:00.0 Network controller: Intel Corporation PRO/Wireless 5100 AGN [Shiloh] Network Connection is low (128) [Network controller]. FAILED [LOW] LowMaxReadReq: Test 1, 2 devices have low MaxReadReq settings. Firmware may have configured these too low. ADVICE: The MaxReadRequest size is set too low and will affect performance. It will provide excellent bus sharing at the cost of bus data transfer rates. Although not a critical issue, it may be worth considering setting the MaxReadRequest size to 256 or 512 to increase throughput on the PCI Express bus. Some drivers (for example the Brocade Fibre Channel driver) allow one to override the firmware settings. Where possible, this BIOS configuration setting is worth increasing it a little more for better performance at a small reduction of bus sharing. ==================================================================================================== PCIe ASPM check. ---------------------------------------------------------------------------------------------------- Test 1 of 2: PCIe ASPM ACPI test. PCIE ASPM is not controlled by Linux kernel. ADVICE: BIOS reports that Linux kernel should not modify ASPM settings that BIOS configured. It can be intentional because hardware vendors identified some capability bugs between the motherboard and the add-on cards. Test 2 of 2: PCIe ASPM registers test. WARNING: Test 2, RP 00h:1Ch.01h L0s not enabled. WARNING: Test 2, RP 00h:1Ch.01h L1 not enabled. WARNING: Test 2, Device 02h:00h.00h L0s not enabled. WARNING: Test 2, Device 02h:00h.00h L1 not enabled. PASSED: Test 2, PCIE aspm setting matched was matched. WARNING: Test 2, RP 00h:1Ch.05h L0s not enabled. WARNING: Test 2, RP 00h:1Ch.05h L1 not enabled. WARNING: Test 2, Device 85h:00h.00h L0s not enabled. WARNING: Test 2, Device 85h:00h.00h L1 not enabled. PASSED: Test 2, PCIE aspm setting matched was matched. ==================================================================================================== Extract and analyse Windows Management Instrumentation (WMI). Test 1 of 2: Check Windows Management Instrumentation in DSDT Found WMI Method WMAA with GUID: 5FB7F034-2C63-45E9-BE91-3D44E2C707E4, Instance 0x01 Found WMI Event, Notifier ID: 0x80, GUID: 95F24279-4D7B-4334-9387-ACCDC67EF61C, Instance 0x01 PASSED: Test 1, GUID 95F24279-4D7B-4334-9387-ACCDC67EF61C is handled by driver hp-wmi (Vendor: HP). Found WMI Event, Notifier ID: 0xa0, GUID: 2B814318-4BE8-4707-9D84-A190A859B5D0, Instance 0x01 FAILED [MEDIUM] WMIUnknownGUID: Test 1, GUID 2B814318-4BE8-4707-9D84-A190A859B5D0 is unknown to the kernel, a driver may need to be implemented for this GUID. ADVICE: A WMI driver probably needs to be written for this event. It can checked for using: wmi_has_guid("2B814318-4BE8-4707-9D84-A190A859B5D0"). One can install a notify handler using wmi_install_notify_handler("2B814318-4BE8-4707-9D84-A190A859B5D0", handler, NULL). http://lwn.net/Articles/391230 describes how to write an appropriate driver. Found WMI Object, Object ID AB, GUID: 05901221-D566-11D1-B2F0-00A0C9062910, Instance 0x01, Flags: 00 Found WMI Method WMBA with GUID: 1F4C91EB-DC5C-460B-951D-C7CB9B4B8D5E, Instance 0x01 Found WMI Object, Object ID BC, GUID: 2D114B49-2DFB-4130-B8FE-4A3C09E75133, Instance 0x7f, Flags: 00 Found WMI Object, Object ID BD, GUID: 988D08E3-68F4-4C35-AF3E-6A1B8106F83C, Instance 0x19, Flags: 00 Found WMI Object, Object ID BE, GUID: 14EA9746-CE1F-4098-A0E0-7045CB4DA745, Instance 0x01, Flags: 00 Found WMI Object, Object ID BF, GUID: 322F2028-0F84-4901-988E-015176049E2D, Instance 0x01, Flags: 00 Found WMI Object, Object ID BG, GUID: 8232DE3D-663D-4327-A8F4-E293ADB9BF05, Instance 0x01, Flags: 00 Found WMI Object, Object ID BH, GUID: 8F1F6436-9F42-42C8-BADC-0E9424F20C9A, Instance 0x00, Flags: 00 Found WMI Object, Object ID BI, GUID: 8F1F6435-9F42-42C8-BADC-0E9424F20C9A, Instance 0x00, Flags: 00 Found WMI Method WMAC with GUID: 7391A661-223A-47DB-A77A-7BE84C60822D, Instance 0x01 Found WMI Object, Object ID BJ, GUID: DF4E63B6-3BBC-4858-9737-C74F82F821F3, Instance 0x05, Flags: 00 ==================================================================================================== Disassemble DSDT to check for _OSI("Linux"). ---------------------------------------------------------------------------------------------------- Test 1 of 1: Disassemble DSDT to check for _OSI("Linux"). This is not strictly a failure mode, it just alerts one that this has been defined in the DSDT and probably should be avoided since the Linux ACPI driver matches onto the Windows _OSI strings { If (_OSI ("Linux")) { Store (0x03E8, OSYS) } If (_OSI ("Windows 2001")) { Store (0x07D1, OSYS) } If (_OSI ("Windows 2001 SP1")) { Store (0x07D1, OSYS) } If (_OSI ("Windows 2001 SP2")) { Store (0x07D2, OSYS) } If (_OSI ("Windows 2006")) { Store (0x07D6, OSYS) } If (LAnd (MPEN, LEqual (OSYS, 0x07D1))) { TRAP (0x01, 0x48) } TRAP (0x03, 0x35) } WARNING: Test 1, DSDT implements a deprecated _OSI("Linux") test. ==================================================================================================== 0 passed, 0 failed, 1 warnings, 0 aborted, 0 skipped, 0 info only. ==================================================================================================== ACPI DSDT Method Semantic Tests. ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP Failed to install global event handler. Test 22 of 93: Check _PSR (Power Source). ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 22, Detected an infinite loop when evaluating method '\_SB_.AC__._PSR'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. PASSED: Test 22, \_SB_.AC__._PSR correctly acquired and released locks 16 times. Test 35 of 93: Check _TMP (Thermal Zone Current Temp). ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 35, Detected an infinite loop when evaluating method '\_TZ_.DTSZ._TMP'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. PASSED: Test 35, \_TZ_.DTSZ._TMP correctly acquired and released locks 14 times. ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 35, Detected an infinite loop when evaluating method '\_TZ_.CPUZ._TMP'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. PASSED: Test 35, \_TZ_.CPUZ._TMP correctly acquired and released locks 10 times. ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 35, Detected an infinite loop when evaluating method '\_TZ_.SKNZ._TMP'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. PASSED: Test 35, \_TZ_.SKNZ._TMP correctly acquired and released locks 10 times. PASSED: Test 35, _TMP correctly returned sane looking value 0x00000b4c (289.2 degrees K) PASSED: Test 35, \_TZ_.BATZ._TMP correctly acquired and released locks 9 times. PASSED: Test 35, _TMP correctly returned sane looking value 0x00000aac (273.2 degrees K) PASSED: Test 35, \_TZ_.FDTZ._TMP correctly acquired and released locks 7 times. Test 46 of 93: Check _DIS (Disable). FAILED [MEDIUM] MethodShouldReturnNothing: Test 46, \_SB_.PCI0.LPCB.SIO_.COM1._DIS returned values, but was expected to return nothing. Object returned: INTEGER: 0x00000000 ADVICE: This probably won't cause any errors, but it should be fixed as the AML code is not conforming to the expected behaviour as described in the ACPI specification. FAILED [MEDIUM] MethodShouldReturnNothing: Test 46, \_SB_.PCI0.LPCB.SIO_.LPT0._DIS returned values, but was expected to return nothing. Object returned: INTEGER: 0x00000000 ADVICE: This probably won't cause any errors, but it should be fixed as the AML code is not conforming to the expected behaviour as described in the ACPI specification. Test 61 of 93: Check _WAK (System Wake). Test _WAK(1) System Wake, State S1. ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 61, Detected an infinite loop when evaluating method '\_WAK'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. Test _WAK(2) System Wake, State S2. ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 61, Detected an infinite loop when evaluating method '\_WAK'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. Test _WAK(3) System Wake, State S3. ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 61, Detected an infinite loop when evaluating method '\_WAK'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. Test _WAK(4) System Wake, State S4. ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 61, Detected an infinite loop when evaluating method '\_WAK'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. Test _WAK(5) System Wake, State S5. ACPICA Exception AE_AML_INFINITE_LOOP during execution of method COMP WARNING: Test 61, Detected an infinite loop when evaluating method '\_WAK'. ADVICE: This may occur because we are emulating the execution in this test environment and cannot handshake with the embedded controller or jump to the BIOS via SMIs. However, the fact that AML code spins forever means that lockup conditions are not being checked for in the AML bytecode. Test 87 of 93: Check _BCL (Query List of Brightness Control Levels Supported). Package has 2 elements: 00: INTEGER: 0x00000000 01: INTEGER: 0x00000000 FAILED [MEDIUM] Method_BCLElementCount: Test 87, Method _BCL should return a package of more than 2 integers, got just 2. Test 88 of 93: Check _BCM (Set Brightness Level). ACPICA Exception AE_AML_PACKAGE_LIMIT during execution of method _BCM FAILED [CRITICAL] AEAMLPackgeLimit: Test 88, Detected error 'Package limit' when evaluating '\_SB_.PCI0.GFX0.DD02._BCM'. ==================================================================================================== ACPI table settings sanity checks. ---------------------------------------------------------------------------------------------------- Test 1 of 1: Check ACPI tables. PASSED: Test 1, Table APIC passed. Table ECDT not present to check. FAILED [MEDIUM] FADT32And64BothDefined: Test 1, FADT 32 bit FIRMWARE_CONTROL is non-zero, and X_FIRMWARE_CONTROL is also non-zero. Section 5.2.9 of the ACPI specification states that if the FIRMWARE_CONTROL is non-zero then X_FIRMWARE_CONTROL must be set to zero. ADVICE: The FADT FIRMWARE_CTRL is a 32 bit pointer that points to the physical memory address of the Firmware ACPI Control Structure (FACS). There is also an extended 64 bit version of this, the X_FIRMWARE_CTRL pointer that also can point to the FACS. Section 5.2.9 of the ACPI specification states that if the X_FIRMWARE_CTRL field contains a non zero value then the FIRMWARE_CTRL field *must* be zero. This error is also detected by the Linux kernel. If FIRMWARE_CTRL and X_FIRMWARE_CTRL are defined, then the kernel just uses the 64 bit version of the pointer. PASSED: Test 1, Table HPET passed. PASSED: Test 1, Table MCFG passed. PASSED: Test 1, Table RSDT passed. PASSED: Test 1, Table RSDP passed. Table SBST not present to check. PASSED: Test 1, Table XSDT passed. ==================================================================================================== Re-assemble DSDT and find syntax errors and warnings. ---------------------------------------------------------------------------------------------------- Test 1 of 2: Disassemble and reassemble DSDT FAILED [HIGH] AMLAssemblerError4043: Test 1, Assembler error in line 2261 Line | AML source ---------------------------------------------------------------------------------------------------- 02258| 0x00000000, // Range Minimum 02259| 0xFEDFFFFF, // Range Maximum 02260| 0x00000000, // Translation Offset 02261| 0x00000000, // Length | ^ | error 4043: Invalid combination of Length and Min/Max fixed flags 02262| ,, _Y0E, AddressRangeMemory, TypeStatic) 02263| DWordMemory (ResourceProducer, PosDecode, MinFixed, MaxFixed, Cacheable, ReadWrite, 02264| 0x00000000, // Granularity ==================================================================================================== ADVICE: (for error #4043): This occurs if the length is zero and just one of the resource MIF/MAF flags are set, or the length is non-zero and resource MIF/MAF flags are both set. These are illegal combinations and need to be fixed. See section 6.4.3.5 Address Space Resource Descriptors of version 4.0a of the ACPI specification for more details. FAILED [HIGH] AMLAssemblerError4050: Test 1, Assembler error in line 2268 Line | AML source ---------------------------------------------------------------------------------------------------- 02265| 0xFEE01000, // Range Minimum 02266| 0xFFFFFFFF, // Range Maximum 02267| 0x00000000, // Translation Offset 02268| 0x011FEFFF, // Length | ^ | error 4050: Length is not equal to fixed Min/Max window 02269| ,, , AddressRangeMemory, TypeStatic) 02270| }) 02271| Method (_CRS, 0, Serialized) ==================================================================================================== ADVICE: (for error #4050): The minimum address is greater than the maximum address. This is illegal. FAILED [HIGH] AMLAssemblerError1104: Test 1, Assembler error in line 8885 Line | AML source ---------------------------------------------------------------------------------------------------- 08882| Method (_DIS, 0, NotSerialized) 08883| { 08884| DSOD (0x02) 08885| Return (0x00) | ^ | warning level 0 1104: Reserved method should not return a value (_DIS) 08886| } 08887| 08888| Method (_SRS, 1, NotSerialized) ==================================================================================================== FAILED [HIGH] AMLAssemblerError1104: Test 1, Assembler error in line 9195 Line | AML source ---------------------------------------------------------------------------------------------------- 09192| Method (_DIS, 0, NotSerialized) 09193| { 09194| DSOD (0x01) 09195| Return (0x00) | ^ | warning level 0 1104: Reserved method should not return a value (_DIS) 09196| } 09197| 09198| Method (_SRS, 1, NotSerialized) ==================================================================================================== FAILED [HIGH] AMLAssemblerError1127: Test 1, Assembler error in line 9242 Line | AML source ---------------------------------------------------------------------------------------------------- 09239| CreateWordField (CRES, \_SB.PCI0.LPCB.SIO.LPT0._CRS._Y21._MAX, MAX2) 09240| CreateByteField (CRES, \_SB.PCI0.LPCB.SIO.LPT0._CRS._Y21._LEN, LEN2) 09241| CreateWordField (CRES, \_SB.PCI0.LPCB.SIO.LPT0._CRS._Y22._INT, IRQ0) 09242| CreateWordField (CRES, \_SB.PCI0.LPCB.SIO.LPT0._CRS._Y23._DMA, DMA0) | ^ | warning level 0 1127: ResourceTag smaller than Field (Tag: 8 bits, Field: 16 bits) 09243| If (RLPD) 09244| { 09245| Store (0x00, Local0) ==================================================================================================== FAILED [HIGH] AMLAssemblerError1128: Test 1, Assembler error in line 18682 Line | AML source ---------------------------------------------------------------------------------------------------- 18679| Store (0x01, Index (DerefOf (Index (Local0, 0x02)), 0x01)) 18680| If (And (WDPE, 0x40)) 18681| { 18682| Wait (\_SB.BEVT, 0x10) | ^ | warning level 0 1128: Result is not used, possible operator timeout will be missed 18683| } 18684| 18685| Store (BRID, Index (DerefOf (Index (Local0, 0x02)), 0x02)) ==================================================================================================== ADVICE: (for warning level 0 #1128): The operation can possibly timeout, and hence the return value indicates an timeout error. However, because the return value is not checked this very probably indicates that the code is buggy. A possible scenario is that a mutex times out and the code attempts to access data in a critical region when it should not. This will lead to undefined behaviour. This should be fixed. Table DSDT (0) reassembly: Found 2 errors, 4 warnings. Test 2 of 2: Disassemble and reassemble SSDT PASSED: Test 2, SSDT (0) reassembly, Found 0 errors, 0 warnings. FAILED [HIGH] AMLAssemblerError1104: Test 2, Assembler error in line 60 Line | AML source ---------------------------------------------------------------------------------------------------- 00057| { 00058| Store (CPDC (Arg0), Local0) 00059| GCAP (Local0) 00060| Return (Local0) | ^ | warning level 0 1104: Reserved method should not return a value (_PDC) 00061| } 00062| 00063| Method (_OSC, 4, NotSerialized) ==================================================================================================== FAILED [HIGH] AMLAssemblerError1104: Test 2, Assembler error in line 174 Line | AML source ---------------------------------------------------------------------------------------------------- 00171| { 00172| Store (\_PR.CPU0.CPDC (Arg0), Local0) 00173| GCAP (Local0) 00174| Return (Local0) | ^ | warning level 0 1104: Reserved method should not return a value (_PDC) 00175| } 00176| 00177| Method (_OSC, 4, NotSerialized) ==================================================================================================== FAILED [HIGH] AMLAssemblerError1104: Test 2, Assembler error in line 244 Line | AML source ---------------------------------------------------------------------------------------------------- 00241| { 00242| Store (\_PR.CPU0.CPDC (Arg0), Local0) 00243| GCAP (Local0) 00244| Return (Local0) | ^ | warning level 0 1104: Reserved method should not return a value (_PDC) 00245| } 00246| 00247| Method (_OSC, 4, NotSerialized) ==================================================================================================== FAILED [HIGH] AMLAssemblerError1104: Test 2, Assembler error in line 290 Line | AML source ---------------------------------------------------------------------------------------------------- 00287| { 00288| Store (\_PR.CPU0.CPDC (Arg0), Local0) 00289| GCAP (Local0) 00290| Return (Local0) | ^ | warning level 0 1104: Reserved method should not return a value (_PDC) 00291| } 00292| 00293| Method (_OSC, 4, NotSerialized) ==================================================================================================== Table SSDT (1) reassembly: Found 0 errors, 4 warnings. PASSED: Test 2, SSDT (2) reassembly, Found 0 errors, 0 warnings. PASSED: Test 2, SSDT (3) reassembly, Found 0 errors, 0 warnings. ==================================================================================================== 3 passed, 10 failed, 0 warnings, 0 aborted, 0 skipped, 0 info only. ==================================================================================================== Critical failures: 1 method test, at 1 log line: 1449: Detected error 'Package limit' when evaluating '\_SB_.PCI0.GFX0.DD02._BCM'. High failures: 11 klog test, at 1 log line: 121: HIGH Kernel message: [ 3.512783] ACPI Error: Method parse/execution failed [\_SB_.PCI0.GFX0._DOD] (Node f7425858), AE_AML_PACKAGE_LIMIT (20110623/psparse-536) syntaxcheck test, at 1 log line: 1668: Assembler error in line 2261 syntaxcheck test, at 1 log line: 1687: Assembler error in line 2268 syntaxcheck test, at 1 log line: 1703: Assembler error in line 8885 syntaxcheck test, at 1 log line: 1716: Assembler error in line 9195 syntaxcheck test, at 1 log line: 1729: Assembler error in line 9242 syntaxcheck test, at 1 log line: 1742: Assembler error in line 18682 syntaxcheck test, at 1 log line: 1766: Assembler error in line 60 syntaxcheck test, at 1 log line: 1779: Assembler error in line 174 syntaxcheck test, at 1 log line: 1792: Assembler error in line 244 syntaxcheck test, at 1 log line: 1805: Assembler error in line 290 Medium failures: 9 mtrr test, at 1 log line: 76: Memory range 0xc0000000 to 0xdfffffff (PCI Bus 0000:00) has incorrect attribute Write-Combining. mtrr test, at 1 log line: 78: Memory range 0xfee01000 to 0xffffffff (PCI Bus 0000:00) has incorrect attribute Write-Protect. msr test, at 1 log line: 165: MSR SYSENTER_ESP (0x175) has 1 inconsistent values across 2 CPUs for (shift: 0 mask: 0xffffffffffffffff). msr test, at 1 log line: 173: MSR MISC_ENABLE (0x1a0) has 1 inconsistent values across 2 CPUs for (shift: 0 mask: 0x400c51889). wmi test, at 1 log line: 528: GUID 2B814318-4BE8-4707-9D84-A190A859B5D0 is unknown to the kernel, a driver may need to be implemented for this GUID. method test, at 1 log line: 1002: \_SB_.PCI0.LPCB.SIO_.COM1._DIS returned values, but was expected to return nothing. method test, at 1 log line: 1011: \_SB_.PCI0.LPCB.SIO_.LPT0._DIS returned values, but was expected to return nothing. method test, at 1 log line: 1443: Method _BCL should return a package of more than 2 integers, got just 2. acpitables test, at 1 log line: 1643: FADT 32 bit FIRMWARE_CONTROL is non-zero, and X_FIRMWARE_CONTROL is also non-zero. Se

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• Conway's Game of Life - C++ and Qt

  - by Jeff Bridge

  I've done all of the layouts and have most of the code written even. But, I'm stuck in two places. 1) I'm not quite sure how to set up the timer. Am I using it correctly in the gridwindow class? And, am I used the timer functions/signals/slots correctly with the other gridwindow functions. 2) In GridWindow's timerFired() function, I'm having trouble checking/creating the vector-vectors. I wrote out in the comments in that function exactly what I am trying to do. Any help would be much appreciated. main.cpp // Main file for running the grid window application. #include <QApplication> #include "gridwindow.h" //#include "timerwindow.h" #include <stdexcept> #include <string> #include <fstream> #include <sstream> #include <iostream> void Welcome(); // Welcome Function - Prints upon running program; outputs program name, student name/id, class section. void Rules(); // Rules Function: Prints the rules for Conway's Game of Life. using namespace std; // A simple main method to create the window class and then pop it up on the screen. int main(int argc, char *argv[]) { Welcome(); // Calls Welcome function to print student/assignment info. Rules(); // Prints Conway's Game Rules. QApplication app(argc, argv); // Creates the overall windowed application. int rows = 25, cols = 35; //The number of rows & columns in the game grid. GridWindow widget(NULL,rows,cols); // Creates the actual window (for the grid). widget.show(); // Shows the window on the screen. return app.exec(); // Goes into visual loop; starts executing GUI. } // Welcome Function: Prints my name/id, my class number, the assignment, and the program name. void Welcome() { cout << endl; cout << "-------------------------------------------------------------------------------------------------" << endl; cout << "Name/ID - Gabe Audick #7681539807" << endl; cout << "Class/Assignment - CSCI-102 Disccusion 29915: Homework Assignment #4" << endl; cout << "-------------------------------------------------------------------------------------------------" << endl << endl; } // Rules Function: Prints the rules for Conway's Game of Life. void Rules() { cout << "Welcome to Conway's Game of Life." << endl; cout << "Game Rules:" << endl; cout << "\t 1) Any living cell with fewer than two living neighbours dies, as if caused by underpopulation." << endl; cout << "\t 2) Any live cell with more than three live neighbours dies, as if by overcrowding." << endl; cout << "\t 3) Any live cell with two or three live neighbours lives on to the next generation." << endl; cout << "\t 4) Any dead cell with exactly three live neighbours becomes a live cell." << endl << endl; cout << "Enjoy." << endl << endl; } gridcell.h // A header file for a class representing a single cell in a grid of cells. #ifndef GRIDCELL_H_ #define GRIDCELL_H_ #include <QPalette> #include <QColor> #include <QPushButton> #include <Qt> #include <QWidget> #include <QFrame> #include <QHBoxLayout> #include <iostream> // An enum representing the two different states a cell can have. enum CellType { DEAD, // DEAD = Dead Cell. --> Color = White. LIVE // LIVE = Living Cell. ---> Color = White. }; /* Class: GridCell. A class representing a single cell in a grid. Each cell is implemented as a QT QFrame that contains a single QPushButton. The button is sized so that it takes up the entire frame. Each cell also keeps track of what type of cell it is based on the CellType enum. */ class GridCell : public QFrame { Q_OBJECT // Macro allowing us to have signals & slots on this object. private: QPushButton* button; // The button inside the cell that gives its clickability. CellType type; // The type of cell (DEAD or LIVE.) public slots: void handleClick(); // Callback for handling a click on the current cell. void setType(CellType type); // Cell type mutator. Calls the "redrawCell" function. signals: void typeChanged(CellType type); // Signal to notify listeners when the cell type has changed. public: GridCell(QWidget *parent = NULL); // Constructor for creating a cell. Takes parent widget or default parent to NULL. virtual ~GridCell(); // Destructor. void redrawCell(); // Redraws cell: Sets new type/color. CellType getType() const; //Simple getter for the cell type. private: Qt::GlobalColor getColorForCellType(); // Helper method. Returns color that cell should be based from its value. }; #endif gridcell.cpp #include <iostream> #include "gridcell.h" #include "utility.h" using namespace std; // Constructor: Creates a grid cell. GridCell::GridCell(QWidget *parent) : QFrame(parent) { this->type = DEAD; // Default: Cell is DEAD (white). setFrameStyle(QFrame::Box); // Set the frame style. This is what gives each box its black border. this->button = new QPushButton(this); //Creates button that fills entirety of each grid cell. this->button->setSizePolicy(QSizePolicy::Expanding,QSizePolicy::Expanding); // Expands button to fill space. this->button->setMinimumSize(19,19); //width,height // Min height and width of button. QHBoxLayout *layout = new QHBoxLayout(); //Creates a simple layout to hold our button and add the button to it. layout->addWidget(this->button); setLayout(layout); layout->setStretchFactor(this->button,1); // Lets the buttons expand all the way to the edges of the current frame with no space leftover layout->setContentsMargins(0,0,0,0); layout->setSpacing(0); connect(this->button,SIGNAL(clicked()),this,SLOT(handleClick())); // Connects clicked signal with handleClick slot. redrawCell(); // Calls function to redraw (set new type for) the cell. } // Basic destructor. GridCell::~GridCell() { delete this->button; } // Accessor for the cell type. CellType GridCell::getType() const { return(this->type); } // Mutator for the cell type. Also has the side effect of causing the cell to be redrawn on the GUI. void GridCell::setType(CellType type) { this->type = type; redrawCell(); } // Handler slot for button clicks. This method is called whenever the user clicks on this cell in the grid. void GridCell::handleClick() { // When clicked on... if(this->type == DEAD) // If type is DEAD (white), change to LIVE (black). type = LIVE; else type = DEAD; // If type is LIVE (black), change to DEAD (white). setType(type); // Sets new type (color). setType Calls redrawCell() to recolor. } // Method to check cell type and return the color of that type. Qt::GlobalColor GridCell::getColorForCellType() { switch(this->type) { default: case DEAD: return Qt::white; case LIVE: return Qt::black; } } // Helper method. Forces current cell to be redrawn on the GUI. Called whenever the setType method is invoked. void GridCell::redrawCell() { Qt::GlobalColor gc = getColorForCellType(); //Find out what color this cell should be. this->button->setPalette(QPalette(gc,gc)); //Force the button in the cell to be the proper color. this->button->setAutoFillBackground(true); this->button->setFlat(true); //Force QT to NOT draw the borders on the button } gridwindow.h // A header file for a QT window that holds a grid of cells. #ifndef GRIDWINDOW_H_ #define GRIDWINDOW_H_ #include <vector> #include <QWidget> #include <QTimer> #include <QGridLayout> #include <QLabel> #include <QApplication> #include "gridcell.h" /* class GridWindow: This is the class representing the whole window that comes up when this program runs. It contains a header section with a title, a middle section of MxN cells and a bottom section with buttons. */ class GridWindow : public QWidget { Q_OBJECT // Macro to allow this object to have signals & slots. private: std::vector<std::vector<GridCell*> > cells; // A 2D vector containing pointers to all the cells in the grid. QLabel *title; // A pointer to the Title text on the window. QTimer *timer; // Creates timer object. public slots: void handleClear(); // Handler function for clicking the Clear button. void handleStart(); // Handler function for clicking the Start button. void handlePause(); // Handler function for clicking the Pause button. void timerFired(); // Method called whenever timer fires. public: GridWindow(QWidget *parent = NULL,int rows=3,int cols=3); // Constructor. virtual ~GridWindow(); // Destructor. std::vector<std::vector<GridCell*> >& getCells(); // Accessor for the array of grid cells. private: QHBoxLayout* setupHeader(); // Helper function to construct the GUI header. QGridLayout* setupGrid(int rows,int cols); // Helper function to constructor the GUI's grid. QHBoxLayout* setupButtonRow(); // Helper function to setup the row of buttons at the bottom. }; #endif gridwindow.cpp #include <iostream> #include "gridwindow.h" using namespace std; // Constructor for window. It constructs the three portions of the GUI and lays them out vertically. GridWindow::GridWindow(QWidget *parent,int rows,int cols) : QWidget(parent) { QHBoxLayout *header = setupHeader(); // Setup the title at the top. QGridLayout *grid = setupGrid(rows,cols); // Setup the grid of colored cells in the middle. QHBoxLayout *buttonRow = setupButtonRow(); // Setup the row of buttons across the bottom. QVBoxLayout *layout = new QVBoxLayout(); // Puts everything together. layout->addLayout(header); layout->addLayout(grid); layout->addLayout(buttonRow); setLayout(layout); } // Destructor. GridWindow::~GridWindow() { delete title; } // Builds header section of the GUI. QHBoxLayout* GridWindow::setupHeader() { QHBoxLayout *header = new QHBoxLayout(); // Creates horizontal box. header->setAlignment(Qt::AlignHCenter); this->title = new QLabel("CONWAY'S GAME OF LIFE",this); // Creates big, bold, centered label (title): "Conway's Game of Life." this->title->setAlignment(Qt::AlignHCenter); this->title->setFont(QFont("Arial", 32, QFont::Bold)); header->addWidget(this->title); // Adds widget to layout. return header; // Returns header to grid window. } // Builds the grid of cells. This method populates the grid's 2D array of GridCells with MxN cells. QGridLayout* GridWindow::setupGrid(int rows,int cols) { QGridLayout *grid = new QGridLayout(); // Creates grid layout. grid->setHorizontalSpacing(0); // No empty spaces. Cells should be contiguous. grid->setVerticalSpacing(0); grid->setSpacing(0); grid->setAlignment(Qt::AlignHCenter); for(int i=0; i < rows; i++) //Each row is a vector of grid cells. { std::vector<GridCell*> row; // Creates new vector for current row. cells.push_back(row); for(int j=0; j < cols; j++) { GridCell *cell = new GridCell(); // Creates and adds new cell to row. cells.at(i).push_back(cell); grid->addWidget(cell,i,j); // Adds to cell to grid layout. Column expands vertically. grid->setColumnStretch(j,1); } grid->setRowStretch(i,1); // Sets row expansion horizontally. } return grid; // Returns grid. } // Builds footer section of the GUI. QHBoxLayout* GridWindow::setupButtonRow() { QHBoxLayout *buttonRow = new QHBoxLayout(); // Creates horizontal box for buttons. buttonRow->setAlignment(Qt::AlignHCenter); // Clear Button - Clears cell; sets them all to DEAD/white. QPushButton *clearButton = new QPushButton("CLEAR"); clearButton->setFixedSize(100,25); connect(clearButton, SIGNAL(clicked()), this, SLOT(handleClear())); buttonRow->addWidget(clearButton); // Start Button - Starts game when user clicks. Or, resumes game after being paused. QPushButton *startButton = new QPushButton("START/RESUME"); startButton->setFixedSize(100,25); connect(startButton, SIGNAL(clicked()), this, SLOT(handleStart())); buttonRow->addWidget(startButton); // Pause Button - Pauses simulation of game. QPushButton *pauseButton = new QPushButton("PAUSE"); pauseButton->setFixedSize(100,25); connect(pauseButton, SIGNAL(clicked()), this, SLOT(handlePause())); buttonRow->addWidget(pauseButton); // Quit Button - Exits program. QPushButton *quitButton = new QPushButton("EXIT"); quitButton->setFixedSize(100,25); connect(quitButton, SIGNAL(clicked()), qApp, SLOT(quit())); buttonRow->addWidget(quitButton); return buttonRow; // Returns bottom of layout. } /* SLOT method for handling clicks on the "clear" button. Receives "clicked" signals on the "Clear" button and sets all cells to DEAD. */ void GridWindow::handleClear() { for(unsigned int row=0; row < cells.size(); row++) // Loops through current rows' cells. { for(unsigned int col=0; col < cells[row].size(); col++) { GridCell *cell = cells[row][col]; // Grab the current cell & set its value to dead. cell->setType(DEAD); } } } /* SLOT method for handling clicks on the "start" button. Receives "clicked" signals on the "start" button and begins game simulation. */ void GridWindow::handleStart() { this->timer = new QTimer(this); // Creates new timer. connect(this->timer, SIGNAL(timeout()), this, SLOT(timerFired())); // Connect "timerFired" method class to the "timeout" signal fired by the timer. this->timer->start(500); // Timer to fire every 500 milliseconds. } /* SLOT method for handling clicks on the "pause" button. Receives "clicked" signals on the "pause" button and stops the game simulation. */ void GridWindow::handlePause() { this->timer->stop(); // Stops the timer. delete this->timer; // Deletes timer. } // Accessor method - Gets the 2D vector of grid cells. std::vector<std::vector<GridCell*> >& GridWindow::getCells() { return this->cells; } void GridWindow::timerFired() { // I'm not sure how to write this code. // I want to take the original vector-vector, and also make a new, empty vector-vector of the same size. // I would then go through the code below with the original vector, and apply the rules to the new vector-vector. // Finally, I would make the new vector-vecotr the original vector-vector. (That would be one step in the simulation.) cout << cells[1][2]; /* for (unsigned int m = 0; m < original.size(); m++) { for (unsigned int n = 0; n < original.at(m).size(); n++) { unsigned int neighbors = 0; //Begin counting number of neighbors. if (original[m-1][n-1].getType() == LIVE) // If a cell next to [i][j] is LIVE, add one to the neighbor count. neighbors += 1; if (original[m-1][n].getType() == LIVE) neighbors += 1; if (original[m-1][n+1].getType() == LIVE) neighbors += 1; if (original[m][n-1].getType() == LIVE) neighbors += 1; if (original[m][n+1].getType() == LIVE) neighbors += 1; if (original[m+1][n-1].getType() == LIVE) neighbors += 1; if (original[m+1][n].getType() == LIVE) neighbors += 1; if (original[m+1][n+1].getType() == LIVE) neighbors += 1; if (original[m][n].getType() == LIVE && neighbors < 2) // Apply game rules to cells: Create new, updated grid with the roundtwo vector. roundtwo[m][n].setType(LIVE); else if (original[m][n].getType() == LIVE && neighbors > 3) roundtwo[m][n].setType(DEAD); else if (original[m][n].getType() == LIVE && (neighbors == 2 || neighbors == 3)) roundtwo[m][n].setType(LIVE); else if (original[m][n].getType() == DEAD && neighbors == 3) roundtwo[m][n].setType(LIVE); } }*/ }

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• Value cannot be null, ArgumentNullException

  - by Wooolie

  I am currently trying to return an array which contains information about a seat at a theate such as Seat number, Name, Price and Status. I am using a combobox where I want to list all vacant or reserved seats based upon choice. When I choose reserved seats in my combobox, I call upon a method using AddRange. This method is supposed to loop through an array containing all seats and their information. If a seat is Vacant, I add it to an array. When all is done, I return this array. However, I am dealing with a ArgumentNullException. MainForm namespace Assignment4 { public partial class MainForm : Form { // private const int totNumberOfSeats = 240; private SeatManager seatMngr; private const int columns = 10; private const int rows = 10; public enum DisplayOptions { AllSeats, VacantSeats, ReservedSeats } public MainForm() { InitializeComponent(); seatMngr = new SeatManager(rows, columns); InitializeGUI(); } /// <summary> /// Fill the listbox with information from the beginning, /// let the user be able to choose from vacant seats. /// </summary> private void InitializeGUI() { rbReserve.Checked = true; txtName.Text = string.Empty; txtPrice.Text = string.Empty; lblTotalSeats.Text = seatMngr.GetNumOfSeats().ToString(); cmbOptions.Items.AddRange(Enum.GetNames(typeof(DisplayOptions))); cmbOptions.SelectedIndex = 0; UpdateGUI(); } /// <summary> /// call on methods ValidateName and ValidatePrice with arguments /// </summary> /// <param name="name"></param> /// <param name="price"></param> /// <returns></returns> private bool ValidateInput(out string name, out double price) { bool nameOK = ValidateName(out name); bool priceOK = ValidatePrice(out price); return nameOK && priceOK; } /// <summary> /// Validate name using inputUtility, show error if input is invalid /// </summary> /// <param name="name"></param> /// <returns></returns> private bool ValidateName(out string name) { name = txtName.Text.Trim(); if (!InputUtility.ValidateString(name)) { //inform user MessageBox.Show("Input of name is Invalid. It can not be empty, " + Environment.NewLine + "and must have at least one character.", " Error!"); txtName.Focus(); txtName.Text = " "; txtName.SelectAll(); return false; } return true; } /// <summary> /// Validate price using inputUtility, show error if input is invalid /// </summary> /// <param name="price"></param> /// <returns></returns> private bool ValidatePrice(out double price) { // show error if input is invalid if (!InputUtility.GetDouble(txtPrice.Text.Trim(), out price, 0)) { //inform user MessageBox.Show("Input of price is Invalid. It can not be less than 0, " + Environment.NewLine + "and must not be empty.", " Error!"); txtPrice.Focus(); txtPrice.Text = " "; txtPrice.SelectAll(); return false; } return true; } /// <summary> /// Check if item is selected in listbox /// </summary> /// <returns></returns> private bool CheckSelectedIndex() { int index = lbSeats.SelectedIndex; if (index < 0) { MessageBox.Show("Please select an item in the box"); return false; } else return true; } /// <summary> /// Call method ReserveOrCancelSeat when button OK is clicked /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void btnOK_Click(object sender, EventArgs e) { ReserveOrCancelSeat(); } /// <summary> /// Reserve or cancel seat depending on choice the user makes. Update GUI after choice. /// </summary> private void ReserveOrCancelSeat() { if (CheckSelectedIndex() == true) { string name = string.Empty; double price = 0.0; int selectedSeat = lbSeats.SelectedIndex; bool reserve = false; bool cancel = false; if (rbReserve.Checked) { DialogResult result = MessageBox.Show("Do you want to continue?", "Approve", MessageBoxButtons.YesNo); if (result == DialogResult.Yes) { if (ValidateInput(out name, out price)) { reserve = seatMngr.ReserveSeat(name, price, selectedSeat); if (reserve == true) { MessageBox.Show("Seat has been reserved"); UpdateGUI(); } else { MessageBox.Show("Seat has already been reserved"); } } } } else { DialogResult result = MessageBox.Show("Do you want to continue?", "Approve", MessageBoxButtons.YesNo); if (result == DialogResult.Yes) { cancel = seatMngr.CancelSeat(selectedSeat); if (cancel == true) { MessageBox.Show("Seat has been cancelled"); UpdateGUI(); } else { MessageBox.Show("Seat is already vacant"); } } } UpdateGUI(); } } /// <summary> /// Update GUI with new information. /// </summary> /// <param name="customerName"></param> /// <param name="price"></param> private void UpdateGUI() { lbSeats.Items.Clear(); lbSeats.Items.AddRange(seatMngr.GetSeatInfoString()); lblVacantSeats.Text = seatMngr.GetNumOfVacant().ToString(); lblReservedSeats.Text = seatMngr.GetNumOfReserved().ToString(); if (rbReserve.Checked) { txtName.Text = string.Empty; txtPrice.Text = string.Empty; } } /// <summary> /// set textboxes to false if cancel reservation button is checked /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void rbCancel_CheckedChanged_1(object sender, EventArgs e) { txtName.Enabled = false; txtPrice.Enabled = false; } /// <summary> /// set textboxes to true if reserved radiobutton is checked /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void rbReserve_CheckedChanged_1(object sender, EventArgs e) { txtName.Enabled = true; txtPrice.Enabled = true; } /// <summary> /// Make necessary changes on the list depending on what choice the user makes. Show only /// what the user wants to see, whether its all seats, reserved seats or vacant seats only. /// </summary> /// <param name="sender"></param> /// <param name="e"></param> private void cmbOptions_SelectedIndexChanged(object sender, EventArgs e) { if (cmbOptions.SelectedIndex == 0 && rbReserve.Checked) //All seats visible. { UpdateGUI(); txtName.Enabled = true; txtPrice.Enabled = true; btnOK.Enabled = true; } else if (cmbOptions.SelectedIndex == 0 && rbCancel.Checked) { UpdateGUI(); txtName.Enabled = false; txtPrice.Enabled = false; btnOK.Enabled = true; } else if (cmbOptions.SelectedIndex == 1) //Only vacant seats visible. { lbSeats.Items.Clear(); lbSeats.Items.AddRange(seatMngr.ReturnVacantSeats()); // Value cannot be null txtName.Enabled = false; txtPrice.Enabled = false; btnOK.Enabled = false; } else if (cmbOptions.SelectedIndex == 2) //Only reserved seats visible. { lbSeats.Items.Clear(); lbSeats.Items.AddRange(seatMngr.ReturnReservedSeats()); // Value cannot be null txtName.Enabled = false; txtPrice.Enabled = false; btnOK.Enabled = false; } } } } SeatManager namespace Assignment4 { class SeatManager { private string[,] nameList = null; private double[,] priceList = null; private string[,] seatList = null; private readonly int totCols; private readonly int totRows; /// <summary> /// Constructor with declarations of size for all arrays. /// </summary> /// <param name="totNumberOfSeats"></param> public SeatManager(int row, int cols) { totCols = cols; totRows = row; nameList = new string[row, cols]; priceList = new double[row, cols]; seatList = new string[row, cols]; for (int rows = 0; rows < row; rows++) { for (int col = 0; col < totCols; col++) { seatList[rows, col] = "Vacant"; } } } /// <summary> /// Check if index is within bounds of the array /// </summary> /// <param name="index"></param> /// <returns></returns> private bool CheckIndex(int index) { if (index >= 0 && index < nameList.Length) return true; else return false; } /// <summary> /// Return total number of seats /// </summary> /// <returns></returns> public int GetNumOfSeats() { int count = 0; for (int rows = 0; rows < totRows; rows++) { for (int cols = 0; cols < totCols; cols++) { count++; } } return count; } /// <summary> /// Calculate and return total number of reserved seats /// </summary> /// <returns></returns> public int GetNumOfReserved() { int totReservedSeats = 0; for (int rows = 0; rows < totRows; rows++) { for (int col = 0; col < totCols; col++) { if (!string.IsNullOrEmpty(nameList[rows, col])) { totReservedSeats++; } } } return totReservedSeats; } /// <summary> /// Calculate and return total number of vacant seats /// </summary> /// <returns></returns> public int GetNumOfVacant() { int totVacantSeats = 0; for (int rows = 0; rows < totRows; rows++) { for (int col = 0; col < totCols; col++) { if (string.IsNullOrEmpty(nameList[rows, col])) { totVacantSeats++; } } } return totVacantSeats; } /// <summary> /// Return formated string with info about the seat, name, price and its status /// </summary> /// <param name="index"></param> /// <returns></returns> public string GetSeatInfoAt(int index) { int cols = ReturnColumn(index); int rows = ReturnRow(index); string strOut = string.Format("{0,2} {1,10} {2,17} {3,20} {4,35:f2}", rows+1, cols+1, seatList[rows, cols], nameList[rows, cols], priceList[rows, cols]); return strOut; } /// <summary> /// Send an array containing all seats in the cinema /// </summary> /// <returns></returns> public string[] GetSeatInfoString() { int count = totRows * totCols; if (count <= 0) return null; string[] strSeatInfoStrings = new string[count]; for (int i = 0; i < totRows * totCols; i++) { strSeatInfoStrings[i] = GetSeatInfoAt(i); } return strSeatInfoStrings; } /// <summary> /// Reserve seat if seat is vacant /// </summary> /// <param name="name"></param> /// <param name="price"></param> /// <param name="index"></param> /// <returns></returns> public bool ReserveSeat(string name, double price, int index) { int cols = ReturnColumn(index); int rows = ReturnRow(index); if (string.IsNullOrEmpty(nameList[rows, cols])) { nameList[rows, cols] = name; priceList[rows, cols] = price; seatList[rows, cols] = "Reserved"; return true; } else return false; } public string[] ReturnVacantSeats() { int totVacantSeats = int.Parse(GetNumOfVacant().ToString()); string[] vacantSeats = new string[totVacantSeats]; for (int i = 0; i < vacantSeats.Length; i++) { if (GetSeatInfoAt(i) == "Vacant") { vacantSeats[i] = GetSeatInfoAt(i); } } return vacantSeats; } public string[] ReturnReservedSeats() { int totReservedSeats = int.Parse(GetNumOfReserved().ToString()); string[] reservedSeats = new string[totReservedSeats]; for (int i = 0; i < reservedSeats.Length; i++) { if (GetSeatInfoAt(i) == "Reserved") { reservedSeats[i] = GetSeatInfoAt(i); } } return reservedSeats; } /// <summary> /// Cancel seat if seat is reserved /// </summary> /// <param name="index"></param> /// <returns></returns> public bool CancelSeat(int index) { int cols = ReturnColumn(index); int rows = ReturnRow(index); if (!string.IsNullOrEmpty(nameList[rows, cols])) { nameList[rows, cols] = ""; priceList[rows, cols] = 0.0; seatList[rows, cols] = "Vacant"; return true; } else { return false; } } /// <summary> /// Convert index to row and return value /// </summary> /// <param name="index"></param> /// <returns></returns> public int ReturnRow(int index) { int vectorRow = index; int row; row = (int)Math.Ceiling((double)(vectorRow / totCols)); return row; } /// <summary> /// Convert index to column and return value /// </summary> /// <param name="index"></param> /// <returns></returns> public int ReturnColumn(int index) { int row = index; int col = row % totCols; return col; } } } In MainForm, this is where I get ArgumentNullException: lbSeats.Items.AddRange(seatMngr.ReturnVacantSeats()); And this is the method where the array is to be returned containing all vacant seats: public string[] ReturnVacantSeats() { int totVacantSeats = int.Parse(GetNumOfVacant().ToString()); string[] vacantSeats = new string[totVacantSeats]; for (int i = 0; i < vacantSeats.Length; i++) { if (GetSeatInfoAt(i) == "Vacant") { vacantSeats[i] = GetSeatInfoAt(i); } } return vacantSeats; }

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• Entity Association Mapping with Code First Part 1 : Mapping Complex Types

  - by mortezam

  Last week the CTP5 build of the new Entity Framework Code First has been released by data team at Microsoft. Entity Framework Code-First provides a pretty powerful code-centric way to work with the databases. When it comes to associations, it brings ultimate flexibility. I’m a big fan of the EF Code First approach and am planning to explain association mapping with code first in a series of blog posts and this one is dedicated to Complex Types. If you are new to Code First approach, you can find a great walkthrough here. In order to build a solid foundation for our discussion, we will start by learning about some of the core concepts around the relationship mapping.   What is Mapping?Mapping is the act of determining how objects and their relationships are persisted in permanent data storage, in our case, relational databases. What is Relationship mapping?A mapping that describes how to persist a relationship (association, aggregation, or composition) between two or more objects. Types of RelationshipsThere are two categories of object relationships that we need to be concerned with when mapping associations. The first category is based on multiplicity and it includes three types: One-to-one relationships: This is a relationship where the maximums of each of its multiplicities is one. One-to-many relationships: Also known as a many-to-one relationship, this occurs when the maximum of one multiplicity is one and the other is greater than one. Many-to-many relationships: This is a relationship where the maximum of both multiplicities is greater than one. The second category is based on directionality and it contains two types: Uni-directional relationships: when an object knows about the object(s) it is related to but the other object(s) do not know of the original object. To put this in EF terminology, when a navigation property exists only on one of the association ends and not on the both. Bi-directional relationships: When the objects on both end of the relationship know of each other (i.e. a navigation property defined on both ends). How Object Relationships Are Implemented in POCO domain models?When the multiplicity is one (e.g. 0..1 or 1) the relationship is implemented by defining a navigation property that reference the other object (e.g. an Address property on User class). When the multiplicity is many (e.g. 0..*, 1..*) the relationship is implemented via an ICollection of the type of other object. How Relational Database Relationships Are Implemented? Relationships in relational databases are maintained through the use of Foreign Keys. A foreign key is a data attribute(s) that appears in one table and must be the primary key or other candidate key in another table. With a one-to-one relationship the foreign key needs to be implemented by one of the tables. To implement a one-to-many relationship we implement a foreign key from the “one table” to the “many table”. We could also choose to implement a one-to-many relationship via an associative table (aka Join table), effectively making it a many-to-many relationship. Introducing the ModelNow, let's review the model that we are going to use in order to implement Complex Type with Code First. It's a simple object model which consist of two classes: User and Address. Each user could have one billing address. The Address information of a User is modeled as a separate class as you can see in the UML model below: In object-modeling terms, this association is a kind of aggregation—a part-of relationship. Aggregation is a strong form of association; it has some additional semantics with regard to the lifecycle of objects. In this case, we have an even stronger form, composition, where the lifecycle of the part is fully dependent upon the lifecycle of the whole. Fine-grained domain models The motivation behind this design was to achieve Fine-grained domain models. In crude terms, fine-grained means “more classes than tables”. For example, a user may have both a billing address and a home address. In the database, you may have a single User table with the columns BillingStreet, BillingCity, and BillingPostalCode along with HomeStreet, HomeCity, and HomePostalCode. There are good reasons to use this somewhat denormalized relational model (performance, for one). In our object model, we can use the same approach, representing the two addresses as six string-valued properties of the User class. But it’s much better to model this using an Address class, where User has the BillingAddress and HomeAddress properties. This object model achieves improved cohesion and greater code reuse and is more understandable. Complex Types: Splitting a Table Across Multiple Types Back to our model, there is no difference between this composition and other weaker styles of association when it comes to the actual C# implementation. But in the context of ORM, there is a big difference: A composed class is often a candidate Complex Type. But C# has no concept of composition—a class or property can’t be marked as a composition. The only difference is the object identifier: a complex type has no individual identity (i.e. no AddressId defined on Address class) which make sense because when it comes to the database everything is going to be saved into one single table. How to implement a Complex Types with Code First Code First has a concept of Complex Type Discovery that works based on a set of Conventions. The convention is that if Code First discovers a class where a primary key cannot be inferred, and no primary key is registered through Data Annotations or the fluent API, then the type will be automatically registered as a complex type. Complex type detection also requires that the type does not have properties that reference entity types (i.e. all the properties must be scalar types) and is not referenced from a collection property on another type. Here is the implementation: public class User{    public int UserId { get; set; }    public string FirstName { get; set; }    public string LastName { get; set; }    public string Username { get; set; }    public Address Address { get; set; }} public class Address {     public string Street { get; set; }     public string City { get; set; }            public string PostalCode { get; set; }        }public class EntityMappingContext : DbContext {     public DbSet<User> Users { get; set; }        } With code first, this is all of the code we need to write to create a complex type, we do not need to configure any additional database schema mapping information through Data Annotations or the fluent API. Database SchemaThe mapping result for this object model is as follows: Limitations of this mappingThere are two important limitations to classes mapped as Complex Types: Shared references is not possible: The Address Complex Type doesn’t have its own database identity (primary key) and so can’t be referred to by any object other than the containing instance of User (e.g. a Shipping class that also needs to reference the same User Address). No elegant way to represent a null reference There is no elegant way to represent a null reference to an Address. When reading from database, EF Code First always initialize Address object even if values in all mapped columns of the complex type are null. This means that if you store a complex type object with all null property values, EF Code First returns a initialized complex type when the owning entity object is retrieved from the database. SummaryIn this post we learned about fine-grained domain models which complex type is just one example of it. Fine-grained is fully supported by EF Code First and is known as the most important requirement for a rich domain model. Complex type is usually the simplest way to represent one-to-one relationships and because the lifecycle is almost always dependent in such a case, it’s either an aggregation or a composition in UML. In the next posts we will revisit the same domain model and will learn about other ways to map a one-to-one association that does not have the limitations of the complex types. References ADO.NET team blog Mapping Objects to Relational Databases Java Persistence with Hibernate

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• Continuous Integration for SQL Server Part II – Integration Testing

  - by Ben Rees

  My previous post, on setting up Continuous Integration for SQL Server databases using GitHub, Bamboo and Red Gate’s tools, covered the first two parts of a simple Database Continuous Delivery process: Putting your database in to a source control system, and, Running a continuous integration process, each time changes are checked in. However there is, of course, a lot more to to Continuous Delivery than that. Specifically, in addition to the above: Putting some actual integration tests in to the CI process (otherwise, they don’t really do much, do they!?), Deploying the database changes with a managed, automated approach, Monitoring what you’ve just put live, to make sure you haven’t broken anything. This post will detail how to set up a very simple pipeline for implementing the first of these (continuous integration testing). NB: A lot of the setup in this post is built on top of the configuration from before, so it might be difficult to implement this post without running through part I first. There’ll then be a third post on automated database deployment followed by a final post dealing with the last item – monitoring changes on the live system. In the previous post, I used a mixture of Red Gate products and other 3rd party software – GitHub and Atlassian Bamboo specifically. This was partly because I believe most people work in an heterogeneous environment, using software from different vendors to suit their purposes and I wanted to show how this could work for this process. For example, you could easily substitute Atlassian’s BitBucket or Stash for GitHub, depending on your needs, or use an alternative CI server such as TeamCity, TFS or Jenkins. However, in this, post, I’ll be mostly using Red Gate products only (other than tSQLt). I would do this, firstly because I work for Red Gate. However, I also think that in the area of Database Delivery processes, nobody else has the offerings to implement this process fully – so I didn’t have any choice!   Background on Continuous Delivery For me, a great source of information on what makes a proper Continuous Delivery process is the Jez Humble and David Farley classic: Continuous Delivery – Reliable Software Releases through Build, Test, and Deployment Automation This book is not of course, primarily about databases, and the process I outline here and in the previous article is a gross simplification of what Jez and David describe (not least because it’s that much harder for databases!). However, a lot of the principles that they describe can be equally applied to database development and, I would argue, should be. As I say however, what I describe here is a very simple version of what would be required for a full production process. A couple of useful resources on handling some of these complexities can be found in the following two references: Refactoring Databases – Evolutionary Database Design, by Scott J Ambler and Pramod J. Sadalage Versioning Databases – Branching and Merging, by Scott Allen In particular, I don’t deal at all with the issues of multiple branches and merging of those branches, an issue made particularly acute by the use of GitHub. The other point worth making is that, in the words of Martin Fowler: Continuous Delivery is about keeping your application in a state where it is always able to deploy into production.   I.e. we are not talking about continuously delivery updates to the production database every time someone checks in an amendment to a stored procedure. That is possible (and what Martin calls Continuous Deployment). However, again, that’s more than I describe in this article. And I doubt I need to remind DBAs or Developers to Proceed with Caution!   Integration Testing Back to something practical. The next stage, building on our set up from the previous article, is to add in some integration tests to the process. As I say, the CI process, though interesting, isn’t enormously useful without some sort of test process running. For this we’ll use the tSQLt framework, an open source framework designed specifically for running SQL Server tests. tSQLt is part of Red Gate’s SQL Test found on http://www.red-gate.com/products/sql-development/sql-test/ or can be downloaded separately from www.tsqlt.org - though I’ll provide a step-by-step guide below for setting this up. Getting tSQLt set up via SQL Test Click on the link http://www.red-gate.com/products/sql-development/sql-test/ and click on the blue Download button to download the Red Gate SQL Test product, if not already installed. Follow the install process for SQL Test to install the SQL Server Management Studio (SSMS) plugin on to your machine, if not already installed. Open SSMS. You should now see SQL Test under the Tools menu:   Clicking this link will give you the basic SQL Test dialogue: As yet, though we’ve installed the SQL Test product we haven’t yet installed the tSQLt test framework on to any particular database. To do this, we need to add our RedGateApp database using this dialogue, by clicking on the + Add Database to SQL Test… link, selecting the RedGateApp database and clicking the Add Database link:   In the next screen, SQL Test describes what will be installed on the database for the tSQLt framework. Also in this dialogue, uncheck the “Add SQL Cop tests” option (shown below). SQL Cop is a great set of pre-defined tests that work within the tSQLt framework to check the general health of your SQL Server database. However, we won’t be using them in this particular simple example: Once you’ve clicked on the OK button, the changes described in the dialogue will be made to your database. Some of these are shown in the left-hand-side below: We’ve now installed the framework. However, we haven’t actually created any tests, so this will be the next step. But, before we proceed, we’ve made an update to our database so should, again check this in to source control, adding comments as required:   Also worth a quick check that your build still runs with the new additions!: (And a quick check of the RedGateAppCI database shows that the changes have been made).   Creating and Testing a Unit Test There are, of course, a lot of very interesting unit tests that you could and should set up for a database. The great thing about the tSQLt framework is that you can write these in SQL. The example I’m going to use here is pretty Mickey Mouse – our database table is going to include some email addresses as reference data and I want to check whether these are all in a correct email format. Nothing clever but it illustrates the process and hopefully shows the method by which more interesting tests could be set up. Adding Reference Data to our Database To start, I want to add some reference data to my database, and have this source controlled (as well as the schema). First of all I need to add some data in to my solitary table – this can be done a number of ways, but I’ll do this in SSMS for simplicity: I then add some reference data to my table: Currently this reference data just exists in the database. For proper integration testing, this needs to form part of the source-controlled version of the database – and so needs to be added to the Git repository. This can be done via SQL Source Control, though first a Primary Key needs to be added to the table. Right click the table, select Design, then right-click on the first “id” row. Then click on “Set Primary Key”: NB: once this change is made, click Save to save the change to the table. Then, to source control this reference data, right click on the table (dbo.Email) and selecting the following option:   In the next screen, link the data in the Email table, by selecting it from the list and clicking “save and close”: We should at this point re-commit the changes (both the addition of the Primary Key, and the data) to the Git repo. NB: From here on, I won’t show screenshots for the GitHub side of things – it’s the same each time: whenever a change is made in SQL Source Control and committed to your local folder, you then need to sync this in the GitHub Windows client (as this is where the build server, Bamboo is taking it from). An interesting point to note here, when these changes are committed in SQL Source Control (right-click database and select “Commit Changes to Source Control..”): The display gives a warning about possibly needing a migration script for the “Add Primary Key” step of the changes. This isn’t actually necessary in this case, but this mechanism would allow you to create override scripts to replace the default change scripts created by the SQL Compare engine (which runs underneath SQL Source Control). Ignoring this message (!), we add a comment and commit the changes to Git. I then sync these, run a build (or the build gets run automatically), and check that the data is being deployed over to the target RedGateAppCI database:   Creating and Running the Test As I mention, the test I’m going to use here is a very simple one - are the email addresses in my reference table valid? This isn’t of course, a full test of email validation (I expect the email addresses I’ve chosen here aren’t really the those of the Fab Four) – but just a very basic check of format used. I’ve taken the relevant SQL from this Stack Overflow article. In SSMS select “SQL Test” from the Tools menu, then click on + New Test: In the next screen, give your new test a name, and also enter a name in the Test Class box (test classes are schemas that help you keep things organised). Also check that the database in which the test is going to be created is correct – RedGateApp in this example: Click “Create Test”. After closing a couple of subsequent dialogues, you’ll see a dummy script for the test, that needs filling in:   We now need to define the SQL for our test. As mentioned before, tSQLt allows you to write your unit tests in T-SQL, and the code I’m going to use here is as below. This needs to be copied and pasted in to the query window, to replace the default given by tSQLt: –  Basic email check test ALTER PROCEDURE [MyChecks].[test Check Email Addresses] AS BEGIN SET NOCOUNT ON         Declare @Output VarChar(max)     Set @Output = ”       SELECT  @Output = @Output + Email +Char(13) + Char(10) FROM dbo.Email WHERE email NOT LIKE ‘%_@__%.__%’       If @Output > ”         Begin             Set @Output = Char(13) + Char(10)                           + @Output             EXEC tSQLt.Fail@Output         End   END;   Once this script is entered, hit execute to add the Stored Procedure to the database. Before committing the test to source control,  it’s worth just checking that it works! For a positive test, click on “SQL Test” from the Tools menu, then click Run Tests. You should see output like the following: - a green tick to indicate success! But of course, what we also need to do is test that this is actually doing something by showing a failed test. Edit one of the email addresses in your table to an incorrect format: Now, re-run the same SQL Test as before and you’ll see the following: Great – we now know that our test is really doing something! You’ll also see a useful error message at the bottom of SSMS: (leave the email address as invalid for now, for the next steps). The next stage is to check this new test in to source control again, by right-clicking on the database and checking in the changes with a commit message (and not forgetting to sync in the GitHub client):   Checking that the Tests are Running as Integration Tests After the changes above are made, and after a build has run on Bamboo (manual or automatic), looking at the Stored Procedures for the RedGateAppCI, the SPROC for the new test has been moved over to the database. However this is not exactly what we were after. We didn’t want to just copy objects from one database to another, but actually run the tests as part of the build/integration test process. I.e. we’re continuously checking any changes we make (in this case, to the reference data emails), to ensure we’re not breaking a test that we’ve set up. The behaviour we want to see is that, if we check in static data that is incorrect (as we did in step 9 above) and we have the tSQLt test set up, then our build in Bamboo should fail. However, re-running the build shows the following: - sadly, a successful build! To make sure the tSQLt tests are run as part of the integration test, we need to amend a switch in the Red Gate CI config file. First, navigate to file sqlCI.targets in your working folder: Edit this document, make the following change, save the document, then commit and sync this change in the GitHub client: <!-- tSQLt tests --> <!-- Optional --> <!-- To run tSQLt tests in source control for the database, enter true. --> <enableTsqlt>true</enableTsqlt> Now, if we re-run the build in Bamboo (NB: I’ve moved to a new server here, hence different address and build number): - superb, a broken build!! The error message isn’t great here, so to get more detailed info, click on the full build log link on this page (below the fold). The interesting part of the log shown is towards the bottom. Pulling out this part:   21-Jun-2013 11:35:19 Build FAILED. 21-Jun-2013 11:35:19 21-Jun-2013 11:35:19 "C:\Users\Administrator\bamboo-home\xml-data\build-dir\RGA-RGP-JOB1\sqlCI.proj" (default target) (1) -> 21-Jun-2013 11:35:19 (sqlCI target) -> 21-Jun-2013 11:35:19 EXEC : sqlCI error occurred: RedGate.Deploy.SqlServerDbPackage.Shared.Exceptions.InvalidSqlException: Test Case Summary: 1 test case(s) executed, 0 succeeded, 1 failed, 0 errored. [C:\Users\Administrator\bamboo-home\xml-data\build-dir\RGA-RGP-JOB1\sqlCI.proj] 21-Jun-2013 11:35:19 EXEC : sqlCI error occurred: [MyChecks].[test Check Email Addresses] failed: [C:\Users\Administrator\bamboo-home\xml-data\build-dir\RGA-RGP-JOB1\sqlCI.proj] 21-Jun-2013 11:35:19 EXEC : sqlCI error occurred: ringo.starr@beatles [C:\Users\Administrator\bamboo-home\xml-data\build-dir\RGA-RGP-JOB1\sqlCI.proj] 21-Jun-2013 11:35:19 EXEC : sqlCI error occurred: [C:\Users\Administrator\bamboo-home\xml-data\build-dir\RGA-RGP-JOB1\sqlCI.proj] 21-Jun-2013 11:35:19 EXEC : sqlCI error occurred: +----------------------+ [C:\Users\Administrator\bamboo-home\xml-data\build-dir\RGA-RGP-JOB1\sqlCI.proj] 21-Jun-2013 11:35:19 EXEC : sqlCI error occurred: |Test Execution Summary| [C:\Users\Administrator\bamboo-home\xml-data\build-dir\RGA-RGP-JOB1\sqlCI.proj]   As a final check, we should make sure that, if we now fix this error, the build succeeds. So in SSMS, I’m going to correct the invalid email address, then check this change in to SQL Source Control (with a comment), commit to GitHub, and re-run the build:   This should have fixed the build: It worked! Summary This has been a very quick run through the implementation of CI for databases, including tSQLt tests to test whether your database updates are working. The next post in this series will focus on automated deployment – we’ve tested our database changes, how can we now deploy these to target sites?  

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• So…is it a Seek or a Scan?

  - by Paul White

  You’re probably most familiar with the terms ‘Seek’ and ‘Scan’ from the graphical plans produced by SQL Server Management Studio (SSMS).  The image to the left shows the most common ones, with the three types of scan at the top, followed by four types of seek.  You might look to the SSMS tool-tip descriptions to explain the differences between them: Not hugely helpful are they?  Both mention scans and ranges (nothing about seeks) and the Index Seek description implies that it will not scan the index entirely (which isn’t necessarily true). Recall also yesterday’s post where we saw two Clustered Index Seek operations doing very different things.  The first Seek performed 63 single-row seeking operations; and the second performed a ‘Range Scan’ (more on those later in this post).  I hope you agree that those were two very different operations, and perhaps you are wondering why there aren’t different graphical plan icons for Range Scans and Seeks?  I have often wondered about that, and the first person to mention it after yesterday’s post was Erin Stellato (twitter | blog): Before we go on to make sense of all this, let’s look at another example of how SQL Server confusingly mixes the terms ‘Scan’ and ‘Seek’ in different contexts.  The diagram below shows a very simple heap table with two columns, one of which is the non-clustered Primary Key, and the other has a non-unique non-clustered index defined on it.  The right hand side of the diagram shows a simple query, it’s associated query plan, and a couple of extracts from the SSMS tool-tip and Properties windows. Notice the ‘scan direction’ entry in the Properties window snippet.  Is this a seek or a scan?  The different references to Scans and Seeks are even more pronounced in the XML plan output that the graphical plan is based on.  This fragment is what lies behind the single Index Seek icon shown above: You’ll find the same confusing references to Seeks and Scans throughout the product and its documentation. Making Sense of Seeks Let’s forget all about scans for a moment, and think purely about seeks.  Loosely speaking, a seek is the process of navigating an index B-tree to find a particular index record, most often at the leaf level.  A seek starts at the root and navigates down through the levels of the index to find the point of interest: Singleton Lookups The simplest sort of seek predicate performs this traversal to find (at most) a single record.  This is the case when we search for a single value using a unique index and an equality predicate.  It should be readily apparent that this type of search will either find one record, or none at all.  This operation is known as a singleton lookup.  Given the example table from before, the following query is an example of a singleton lookup seek: Sadly, there’s nothing in the graphical plan or XML output to show that this is a singleton lookup – you have to infer it from the fact that this is a single-value equality seek on a unique index.  The other common examples of a singleton lookup are bookmark lookups – both the RID and Key Lookup forms are singleton lookups (an RID lookup finds a single record in a heap from the unique row locator, and a Key Lookup does much the same thing on a clustered table).  If you happen to run your query with STATISTICS IO ON, you will notice that ‘Scan Count’ is always zero for a singleton lookup. Range Scans The other type of seek predicate is a ‘seek plus range scan’, which I will refer to simply as a range scan.  The seek operation makes an initial descent into the index structure to find the first leaf row that qualifies, and then performs a range scan (either backwards or forwards in the index) until it reaches the end of the scan range. The ability of a range scan to proceed in either direction comes about because index pages at the same level are connected by a doubly-linked list – each page has a pointer to the previous page (in logical key order) as well as a pointer to the following page.  The doubly-linked list is represented by the green and red dotted arrows in the index diagram presented earlier.  One subtle (but important) point is that the notion of a ‘forward’ or ‘backward’ scan applies to the logical key order defined when the index was built.  In the present case, the non-clustered primary key index was created as follows: CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col ASC) ) ; Notice that the primary key index specifies an ascending sort order for the single key column.  This means that a forward scan of the index will retrieve keys in ascending order, while a backward scan would retrieve keys in descending key order.  If the index had been created instead on key_col DESC, a forward scan would retrieve keys in descending order, and a backward scan would return keys in ascending order. A range scan seek predicate may have a Start condition, an End condition, or both.  Where one is missing, the scan starts (or ends) at one extreme end of the index, depending on the scan direction.  Some examples might help clarify that: the following diagram shows four queries, each of which performs a single seek against a column holding every integer from 1 to 100 inclusive.  The results from each query are shown in the blue columns, and relevant attributes from the Properties window appear on the right: Query 1 specifies that all key_col values less than 5 should be returned in ascending order.  The query plan achieves this by seeking to the start of the index leaf (there is no explicit starting value) and scanning forward until the End condition (key_col < 5) is no longer satisfied (SQL Server knows it can stop looking as soon as it finds a key_col value that isn’t less than 5 because all later index entries are guaranteed to sort higher). Query 2 asks for key_col values greater than 95, in descending order.  SQL Server returns these results by seeking to the end of the index, and scanning backwards (in descending key order) until it comes across a row that isn’t greater than 95.  Sharp-eyed readers may notice that the end-of-scan condition is shown as a Start range value.  This is a bug in the XML show plan which bubbles up to the Properties window – when a backward scan is performed, the roles of the Start and End values are reversed, but the plan does not reflect that.  Oh well. Query 3 looks for key_col values that are greater than or equal to 10, and less than 15, in ascending order.  This time, SQL Server seeks to the first index record that matches the Start condition (key_col >= 10) and then scans forward through the leaf pages until the End condition (key_col < 15) is no longer met. Query 4 performs much the same sort of operation as Query 3, but requests the output in descending order.  Again, we have to mentally reverse the Start and End conditions because of the bug, but otherwise the process is the same as always: SQL Server finds the highest-sorting record that meets the condition ‘key_col < 25’ and scans backward until ‘key_col >= 20’ is no longer true. One final point to note: seek operations always have the Ordered: True attribute.  This means that the operator always produces rows in a sorted order, either ascending or descending depending on how the index was defined, and whether the scan part of the operation is forward or backward.  You cannot rely on this sort order in your queries of course (you must always specify an ORDER BY clause if order is important) but SQL Server can make use of the sort order internally.  In the four queries above, the query optimizer was able to avoid an explicit Sort operator to honour the ORDER BY clause, for example. Multiple Seek Predicates As we saw yesterday, a single index seek plan operator can contain one or more seek predicates.  These seek predicates can either be all singleton seeks or all range scans – SQL Server does not mix them.  For example, you might expect the following query to contain two seek predicates, a singleton seek to find the single record in the unique index where key_col = 10, and a range scan to find the key_col values between 15 and 20: SELECT key_col FROM dbo.Example WHERE key_col = 10 OR key_col BETWEEN 15 AND 20 ORDER BY key_col ASC ; In fact, SQL Server transforms the singleton seek (key_col = 10) to the equivalent range scan, Start:[key_col >= 10], End:[key_col <= 10].  This allows both range scans to be evaluated by a single seek operator.  To be clear, this query results in two range scans: one from 10 to 10, and one from 15 to 20. Final Thoughts That’s it for today – tomorrow we’ll look at monitoring singleton lookups and range scans, and I’ll show you a seek on a heap table. Yes, a seek.  On a heap.  Not an index! If you would like to run the queries in this post for yourself, there’s a script below.  Thanks for reading! IF OBJECT_ID(N'dbo.Example', N'U') IS NOT NULL BEGIN DROP TABLE dbo.Example; END ; -- Test table is a heap -- Non-clustered primary key on 'key_col' CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col) ) ; -- Non-unique non-clustered index on the 'data' column CREATE NONCLUSTERED INDEX [IX dbo.Example data] ON dbo.Example (data) ; -- Add 100 rows INSERT dbo.Example WITH (TABLOCKX) ( key_col, data ) SELECT key_col = V.number, data = V.number FROM master.dbo.spt_values AS V WHERE V.[type] = N'P' AND V.number BETWEEN 1 AND 100 ; -- ================ -- Singleton lookup -- ================ ; -- Single value equality seek in a unique index -- Scan count = 0 when STATISTIS IO is ON -- Check the XML SHOWPLAN SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col = 32 ; -- =========== -- Range Scans -- =========== ; -- Query 1 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col <= 5 ORDER BY E.key_col ASC ; -- Query 2 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col > 95 ORDER BY E.key_col DESC ; -- Query 3 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col >= 10 AND E.key_col < 15 ORDER BY E.key_col ASC ; -- Query 4 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col >= 20 AND E.key_col < 25 ORDER BY E.key_col DESC ; -- Final query (singleton + range = 2 range scans) SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col = 10 OR E.key_col BETWEEN 15 AND 20 ORDER BY E.key_col ASC ; -- === TIDY UP === DROP TABLE dbo.Example; © 2011 Paul White email: [email protected] twitter: @SQL_Kiwi

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• SQL SERVER – Weekly Series – Memory Lane – #039

  - by Pinal Dave

  Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 FQL – Facebook Query Language Facebook list following advantages of FQL: Condensed XML reduces bandwidth and parsing costs. More complex requests can reduce the number of requests necessary. Provides a single consistent, unified interface for all of your data. It’s fun! UDF – Get the Day of the Week Function The day of the week can be retrieved in SQL Server by using the DatePart function. The value returned by the function is between 1 (Sunday) and 7 (Saturday). To convert this to a string representing the day of the week, use a CASE statement. UDF – Function to Get Previous And Next Work Day – Exclude Saturday and Sunday While reading ColdFusion blog of Ben Nadel Getting the Previous Day In ColdFusion, Excluding Saturday And Sunday, I realize that I use similar function on my SQL Server Database. This function excludes the Weekends (Saturday and Sunday), and it gets previous as well as next work day. Complete Series of SQL Server Interview Questions and Answers Data Warehousing Interview Questions and Answers – Introduction Data Warehousing Interview Questions and Answers – Part 1 Data Warehousing Interview Questions and Answers – Part 2 Data Warehousing Interview Questions and Answers – Part 3 Data Warehousing Interview Questions and Answers Complete List Download 2008 Introduction to Log Viewer In SQL Server all the windows event logs can be seen along with SQL Server logs. Interface for all the logs is same and can be launched from the same place. This log can be exported and filtered as well. DBCC SHRINKFILE Takes Long Time to Run If you are DBA who are involved with Database Maintenance and file group maintenance, you must have experience that many times DBCC SHRINKFILE operations takes a long time but any other operations with Database are relatively quicker. mssqlsystemresource – Resource Database The purpose of resource database is to facilitates upgrading to the new version of SQL Server without any hassle. In previous versions whenever version of SQL Server was upgraded all the previous version system objects needs to be dropped and new version system objects to be created. 2009 Puzzle – Write Script to Generate Primary Key and Foreign Key In SQL Server Management Studio (SSMS), there is no option to script all the keys. If one is required to script keys they will have to manually script each key one at a time. If database has many tables, generating one key at a time can be a very intricate task. I want to throw a question to all of you if any of you have scripts for the same purpose. Maximizing View of SQL Server Management Studio – Full Screen – New Screen I had explained the following two different methods: 1) Open Results in Separate Tab - This is a very interesting method as result pan shows up in a different tab instead of the splitting screen horizontally. 2) Open SSMS in Full Screen - This works always and to its best. Not many people are aware of this method; hence, very few people use it to enhance performance. 2010 Find Queries using Parallelism from Cached Plan T-SQL script gets all the queries and their execution plan where parallelism operations are kicked up. Pay attention there is TOP 10 is used, if you have lots of transactional operations, I suggest that you change TOP 10 to TOP 50 This is the list of the all the articles in the series of computed columns. SQL SERVER – Computed Column – PERSISTED and Storage This article talks about how computed columns are created and why they take more storage space than before. SQL SERVER – Computed Column – PERSISTED and Performance This article talks about how PERSISTED columns give better performance than non-persisted columns. SQL SERVER – Computed Column – PERSISTED and Performance – Part 2 This article talks about how non-persisted columns give better performance than PERSISTED columns. SQL SERVER – Computed Column and Performance – Part 3 This article talks about how Index improves the performance of Computed Columns. SQL SERVER – Computed Column – PERSISTED and Storage – Part 2 This article talks about how creating index on computed column does not grow the row length of table. SQL SERVER – Computed Columns – Index and Performance This article summarized all the articles related to computed columns. 2011 SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Data Warehousing Concepts – Day 21 of 31 What is Data Warehousing? What is Business Intelligence (BI)? What is a Dimension Table? What is Dimensional Modeling? What is a Fact Table? What are the Fundamental Stages of Data Warehousing? What are the Different Methods of Loading Dimension tables? Describes the Foreign Key Columns in Fact Table and Dimension Table? What is Data Mining? What is the Difference between a View and a Materialized View? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Data Warehousing Concepts – Day 22 of 31 What is OLTP? What is OLAP? What is the Difference between OLTP and OLAP? What is ODS? What is ER Diagram? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Data Warehousing Concepts – Day 23 of 31 What is ETL? What is VLDB? Is OLTP Database is Design Optimal for Data Warehouse? If denormalizing improves Data Warehouse Processes, then why is the Fact Table is in the Normal Form? What are Lookup Tables? What are Aggregate Tables? What is Real-Time Data-Warehousing? What are Conformed Dimensions? What is a Conformed Fact? How do you Load the Time Dimension? What is a Level of Granularity of a Fact Table? What are Non-Additive Facts? What is a Factless Facts Table? What are Slowly Changing Dimensions (SCD)? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Data Warehousing Concepts – Day 24 of 31 What is Hybrid Slowly Changing Dimension? What is BUS Schema? What is a Star Schema? What Snow Flake Schema? Differences between the Star and Snowflake Schema? What is Difference between ER Modeling and Dimensional Modeling? What is Degenerate Dimension Table? Why is Data Modeling Important? What is a Surrogate Key? What is Junk Dimension? What is a Data Mart? What is the Difference between OLAP and Data Warehouse? What is a Cube and Linked Cube with Reference to Data Warehouse? What is Snapshot with Reference to Data Warehouse? What is Active Data Warehousing? What is the Difference between Data Warehousing and Business Intelligence? What is MDS? Explain the Paradigm of Bill Inmon and Ralph Kimball. SQL SERVER – Azure Interview Questions and Answers – Guest Post by Paras Doshi – Day 25 of 31 Paras Doshi has submitted 21 interesting question and answers for SQL Azure. 1.What is SQL Azure? 2.What is cloud computing? 3.How is SQL Azure different than SQL server? 4.How many replicas are maintained for each SQL Azure database? 5.How can we migrate from SQL server to SQL Azure? 6.Which tools are available to manage SQL Azure databases and servers? 7.Tell me something about security and SQL Azure. 8.What is SQL Azure Firewall? 9.What is the difference between web edition and business edition? 10.How do we synchronize On Premise SQL server with SQL Azure? 11.How do we Backup SQL Azure Data? 12.What is the current pricing model of SQL Azure? 13.What is the current limitation of the size of SQL Azure DB? 14.How do you handle datasets larger than 50 GB? 15.What happens when the SQL Azure database reaches Max Size? 16.How many databases can we create in a single server? 17.How many servers can we create in a single subscription? 18.How do you improve the performance of a SQL Azure Database? 19.What is code near application topology? 20.What were the latest updates to SQL Azure service? 21.When does a workload on SQL Azure get throttled? SQL SERVER – Interview Questions and Answers – Guest Post by Malathi Mahadevan – Day 26 of 31 Malachi had asked a simple question which has several answers. Each answer makes you think and ponder about the reality of the IT world. Look at the simple question – ‘What is the toughest challenge you have faced in your present job and how did you handle it’? and its various answers. Each answer has its own story. SQL SERVER – Interview Questions and Answers – Guest Post by Rick Morelan – Day 27 of 31 Rick Morelan of Joes2Pros has written an excellent blog post on the subject how to find top N values. Most people are fully aware of how the TOP keyword works with a SELECT statement. After years preparing so many students to pass the SQL Certification I noticed they were pretty well prepared for job interviews too. Yes, they would do well in the interview but not great. There seemed to be a few questions that would come up repeatedly for almost everyone. Rick addresses similar questions in his lucid writing skills. 2012 Observation of Top with Index and Order of Resultset SQL Server has lots of things to learn and share. It is amazing to see how people evaluate and understand different techniques and styles differently when implementing. The real reason may be absolutely different but we may blame something totally different for the incorrect results. Read the blog post to learn more. How do I Record Video and Webcast How to Convert Hex to Decimal or INT Earlier I asked regarding a question about how to convert Hex to Decimal. I promised that I will post an answer with Due Credit to the author but never got around to post a blog post around it. Read the original post over here SQL SERVER – Question – How to Convert Hex to Decimal. Query to Get Unique Distinct Data Based on Condition – Eliminate Duplicate Data from Resultset The natural reaction will be to suggest DISTINCT or GROUP BY. However, not all the questions can be solved by DISTINCT or GROUP BY. Let us see the following example, where a user wanted only latest records to be displayed. Let us see the example to understand further. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Get XML from Server for Use on Windows Phone

  - by psheriff

  When working with mobile devices you always need to take into account bandwidth usage and power consumption. If you are constantly connecting to a server to retrieve data for an input screen, then you might think about moving some of that data down to the phone and cache the data on the phone. An example would be a static list of US State Codes that you are asking the user to select from. Since this is data that does not change very often, this is one set of data that would be great to cache on the phone. Since the Windows Phone does not have an embedded database, you can just use an XML string stored in Isolated Storage. Of course, then you need to figure out how to get data down to the phone. You can either ship it with the application, or connect and retrieve the data from your server one time and thereafter cache it and retrieve it from the cache. In this blog post you will see how to create a WCF service to retrieve data from a Product table in a database and send that data as XML to the phone and store it in Isolated Storage. You will then read that data from Isolated Storage using LINQ to XML and display it in a ListBox. Step 1: Create a Windows Phone Application The first step is to create a Windows Phone application called WP_GetXmlFromDataSet (or whatever you want to call it). On the MainPage.xaml add the following XAML within the “ContentPanel” grid: <StackPanel>  <Button Name="btnGetXml"          Content="Get XML"          Click="btnGetXml_Click" />  <Button Name="btnRead"          Content="Read XML"          IsEnabled="False"          Click="btnRead_Click" />  <ListBox Name="lstData"            Height="430"            ItemsSource="{Binding}"            DisplayMemberPath="ProductName" /></StackPanel> Now it is time to create the WCF Service Application that you will call to get the XML from a table in a SQL Server database. Step 2: Create a WCF Service Application Add a new project to your solution called WP_GetXmlFromDataSet.Services. Delete the IService1.* and Service1.* files and the App_Data folder, as you don’t generally need these items. Add a new WCF Service class called ProductService. In the IProductService class modify the void DoWork() method with the following code: [OperationContract]string GetProductXml(); Open the code behind in the ProductService.svc and create the GetProductXml() method. This method (shown below) will connect up to a database and retrieve data from a Product table. public string GetProductXml(){  string ret = string.Empty;  string sql = string.Empty;  SqlDataAdapter da;  DataSet ds = new DataSet();   sql = "SELECT ProductId, ProductName,";  sql += " IntroductionDate, Price";  sql += " FROM Product";   da = new SqlDataAdapter(sql,    ConfigurationManager.ConnectionStrings["Sandbox"].ConnectionString);   da.Fill(ds);   // Create Attribute based XML  foreach (DataColumn col in ds.Tables[0].Columns)  {    col.ColumnMapping = MappingType.Attribute;  }   ds.DataSetName = "Products";  ds.Tables[0].TableName = "Product";  ret = ds.GetXml();   return ret;} After retrieving the data from the Product table using a DataSet, you will want to set each column’s ColumnMapping property to Attribute. Using attribute based XML will make the data transferred across the wire a little smaller. You then set the DataSetName property to the top-level element name you want to assign to the XML. You then set the TableName property on the DataTable to the name you want each element to be in your XML. The last thing you need to do is to call the GetXml() method on the DataSet object which will return an XML string of the data in your DataSet object. This is the value that you will return from the service call. The XML that is returned from the above call looks like the following: <Products>  <Product ProductId="1"           ProductName="PDSA .NET Productivity Framework"           IntroductionDate="9/3/2010"           Price="5000" />  <Product ProductId="3"           ProductName="Haystack Code Generator for .NET"           IntroductionDate="7/1/2010"           Price="599.00" />  ...  ...  ... </Products> The GetProductXml() method uses a connection string from the Web.Config file, so add a <connectionStrings> element to the Web.Config file in your WCF Service application. Modify the settings shown below as needed for your server and database name. <connectionStrings>  <add name="Sandbox"        connectionString="Server=Localhost;Database=Sandbox;                         Integrated Security=Yes"/></connectionStrings> The Product Table You will need a Product table that you can read data from. I used the following structure for my product table. Add any data you want to this table after you create it in your database. CREATE TABLE Product(  ProductId int PRIMARY KEY IDENTITY(1,1) NOT NULL,  ProductName varchar(50) NOT NULL,  IntroductionDate datetime NULL,  Price money NULL) Step 3: Connect to WCF Service from Windows Phone Application Back in your Windows Phone application you will now need to add a Service Reference to the WCF Service application you just created. Right-mouse click on the Windows Phone Project and choose Add Service Reference… from the context menu. Click on the Discover button. In the Namespace text box enter “ProductServiceRefrence”, then click the OK button. If you entered everything correctly, Visual Studio will generate some code that allows you to connect to your Product service. On the MainPage.xaml designer window double click on the Get XML button to generate the Click event procedure for this button. In the Click event procedure make a call to a GetXmlFromServer() method. This method will also need a “Completed” event procedure to be written since all communication with a WCF Service from Windows Phone must be asynchronous.  Write these two methods as follows: private const string KEY_NAME = "ProductData"; private void GetXmlFromServer(){  ProductServiceClient client = new ProductServiceClient();   client.GetProductXmlCompleted += new     EventHandler<GetProductXmlCompletedEventArgs>      (client_GetProductXmlCompleted);   client.GetProductXmlAsync();  client.CloseAsync();} void client_GetProductXmlCompleted(object sender,                                   GetProductXmlCompletedEventArgs e){  // Store XML data in Isolated Storage  IsolatedStorageSettings.ApplicationSettings[KEY_NAME] = e.Result;   btnRead.IsEnabled = true;} As you can see, this is a fairly standard call to a WCF Service. In the Completed event you get the Result from the event argument, which is the XML, and store it into Isolated Storage using the IsolatedStorageSettings.ApplicationSettings class. Notice the constant that I added to specify the name of the key. You will use this constant later to read the data from Isolated Storage. Step 4: Create a Product Class Even though you stored XML data into Isolated Storage when you read that data out you will want to convert each element in the XML file into an actual Product object. This means that you need to create a Product class in your Windows Phone application. Add a Product class to your project that looks like the code below: public class Product{  public string ProductName{ get; set; }  public int ProductId{ get; set; }  public DateTime IntroductionDate{ get; set; }  public decimal Price{ get; set; }} Step 5: Read Settings from Isolated Storage Now that you have the XML data stored in Isolated Storage, it is time to use it. Go back to the MainPage.xaml design view and double click on the Read XML button to generate the Click event procedure. From the Click event procedure call a method named ReadProductXml().Create this method as shown below: private void ReadProductXml(){  XElement xElem = null;   if (IsolatedStorageSettings.ApplicationSettings.Contains(KEY_NAME))  {    xElem = XElement.Parse(     IsolatedStorageSettings.ApplicationSettings[KEY_NAME].ToString());     // Create a list of Product objects    var products =         from prod in xElem.Descendants("Product")        orderby prod.Attribute("ProductName").Value        select new Product        {          ProductId = Convert.ToInt32(prod.Attribute("ProductId").Value),          ProductName = prod.Attribute("ProductName").Value,          IntroductionDate =             Convert.ToDateTime(prod.Attribute("IntroductionDate").Value),          Price = Convert.ToDecimal(prod.Attribute("Price").Value)        };     lstData.DataContext = products;  }} The ReadProductXml() method checks to make sure that the key name that you saved your XML as exists in Isolated Storage prior to trying to open it. If the key name exists, then you retrieve the value as a string. Use the XElement’s Parse method to convert the XML string to a XElement object. LINQ to XML is used to iterate over each element in the XElement object and create a new Product object from each attribute in your XML file. The LINQ to XML code also orders the XML data by the ProductName. After the LINQ to XML code runs you end up with an IEnumerable collection of Product objects in the variable named “products”. You assign this collection of product data to the DataContext of the ListBox you created in XAML. The DisplayMemberPath property of the ListBox is set to “ProductName” so it will now display the product name for each row in your products collection. Summary In this article you learned how to retrieve an XML string from a table in a database, return that string across a WCF Service and store it into Isolated Storage on your Windows Phone. You then used LINQ to XML to create a collection of Product objects from the data stored and display that data in a Windows Phone list box. This same technique can be used in Silverlight or WPF applications too. NOTE: You can download the complete sample code at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "Get XML From Server for Use on Windows Phone" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free video on Silverlight entitled Silverlight XAML for the Complete Novice - Part 1.  

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• Windows Azure: Major Updates for Mobile Backend Development

  - by ScottGu

  This week we released some great updates to Windows Azure that make it significantly easier to develop mobile applications that use the cloud. These new capabilities include: Mobile Services: Custom API support Mobile Services: Git Source Control support Mobile Services: Node.js NPM Module support Mobile Services: A .NET API via NuGet Mobile Services and Web Sites: Free 20MB SQL Database Option for Mobile Services and Web Sites Mobile Notification Hubs: Android Broadcast Push Notification Support All of these improvements are now available to use immediately (note: some are still in preview).  Below are more details about them. Mobile Services: Custom APIs, Git Source Control, and NuGet Windows Azure Mobile Services provides the ability to easily stand up a mobile backend that can be used to support your Windows 8, Windows Phone, iOS, Android and HTML5 client applications.  Starting with the first preview we supported the ability to easily extend your data backend logic with server side scripting that executes as part of client-side CRUD operations against your cloud back data tables. With today’s update we are extending this support even further and introducing the ability for you to also create and expose Custom APIs from your Mobile Service backend, and easily publish them to your Mobile clients without having to associate them with a data table. This capability enables a whole set of new scenarios – including the ability to work with data sources other than SQL Databases (for example: Table Services or MongoDB), broker calls to 3rd party APIs, integrate with Windows Azure Queues or Service Bus, work with custom non-JSON payloads (e.g. Windows Periodic Notifications), route client requests to services back on-premises (e.g. with the new Windows Azure BizTalk Services), or simply implement functionality that doesn’t correspond to a database operation.  The custom APIs can be written in server-side JavaScript (using Node.js) and can use Node’s NPM packages.  We will also be adding support for custom APIs written using .NET in the future as well. Creating a Custom API Adding a custom API to an existing Mobile Service is super easy.  Using the Windows Azure Management Portal you can now simply click the new “API” tab with your Mobile Service, and then click the “Create a Custom API” button to create a new Custom API within it: Give the API whatever name you want to expose, and then choose the security permissions you’d like to apply to the HTTP methods you expose within it.  You can easily lock down the HTTP verbs to your Custom API to be available to anyone, only those who have a valid application key, only authenticated users, or administrators.  Mobile Services will then enforce these permissions without you having to write any code: When you click the ok button you’ll see the new API show up in the API list.  Selecting it will enable you to edit the default script that contains some placeholder functionality: Today’s release enables Custom APIs to be written using Node.js (we will support writing Custom APIs in .NET as well in a future release), and the Custom API programming model follows the Node.js convention for modules, which is to export functions to handle HTTP requests. The default script above exposes functionality for an HTTP POST request. To support a GET, simply change the export statement accordingly.  Below is an example of some code for reading and returning data from Windows Azure Table Storage using the Azure Node API: After saving the changes, you can now call this API from any Mobile Service client application (including Windows 8, Windows Phone, iOS, Android or HTML5 with CORS). Below is the code for how you could invoke the API asynchronously from a Windows Store application using .NET and the new InvokeApiAsync method, and data-bind the results to control within your XAML:     private async void RefreshTodoItems() {         var results = await App.MobileService.InvokeApiAsync<List<TodoItem>>("todos", HttpMethod.Get, parameters: null);         ListItems.ItemsSource = new ObservableCollection<TodoItem>(results);     }    Integrating authentication and authorization with Custom APIs is really easy with Mobile Services. Just like with data requests, custom API requests enjoy the same built-in authentication and authorization support of Mobile Services (including integration with Microsoft ID, Google, Facebook and Twitter authentication providers), and it also enables you to easily integrate your Custom API code with other Mobile Service capabilities like push notifications, logging, SQL, etc. Check out our new tutorials to learn more about to use new Custom API support, and starting adding them to your app today. Mobile Services: Git Source Control Support Today’s Mobile Services update also enables source control integration with Git.  The new source control support provides a Git repository as part your Mobile Service, and it includes all of your existing Mobile Service scripts and permissions. You can clone that git repository on your local machine, make changes to any of your scripts, and then easily deploy the mobile service to production using Git. This enables a really great developer workflow that works on any developer machine (Windows, Mac and Linux). To use the new support, navigate to the dashboard for your mobile service and select the Set up source control link: If this is your first time enabling Git within Windows Azure, you will be prompted to enter the credentials you want to use to access the repository: Once you configure this, you can switch to the configure tab of your Mobile Service and you will see a Git URL you can use to use your repository: You can use this URL to clone the repository locally from your favorite command line: > git clone https://scottgutodo.scm.azure-mobile.net/ScottGuToDo.git Below is the directory structure of the repository: As you can see, the repository contains a service folder with several subfolders. Custom API scripts and associated permissions appear under the api folder as .js and .json files respectively (the .json files persist a JSON representation of the security settings for your endpoints). Similarly, table scripts and table permissions appear as .js and .json files, but since table scripts are separate per CRUD operation, they follow the naming convention of <tablename>.<operationname>.js. Finally, scheduled job scripts appear in the scheduler folder, and the shared folder is provided as a convenient location for you to store code shared by multiple scripts and a few miscellaneous things such as the APNS feedback script. Lets modify the table script todos.js file so that we have slightly better error handling when an exception occurs when we query our Table service: todos.js tableService.queryEntities(query, function(error, todoItems){     if (error) {         console.error("Error querying table: " + error);         response.send(500);     } else {         response.send(200, todoItems);     }        }); Save these changes, and now back in the command line prompt commit the changes and push them to the Mobile Services: > git add . > git commit –m "better error handling in todos.js" > git push Once deployment of the changes is complete, they will take effect immediately, and you will also see the changes be reflected in the portal: With the new Source Control feature, we’re making it really easy for you to edit your mobile service locally and push changes in an atomic fashion without sacrificing ease of use in the Windows Azure Portal. Mobile Services: NPM Module Support The new Mobile Services source control support also allows you to add any Node.js module you need in the scripts beyond the fixed set provided by Mobile Services. For example, you can easily switch to use Mongo instead of Windows Azure table in our example above. Set up Mongo DB by either purchasing a MongoLab subscription (which provides MongoDB as a Service) via the Windows Azure Store or set it up yourself on a Virtual Machine (either Windows or Linux). Then go the service folder of your local git repository and run the following command: > npm install mongoose This will add the Mongoose module to your Mobile Service scripts.  After that you can use and reference the Mongoose module in your custom API scripts to access your Mongo database: var mongoose = require('mongoose'); var schema = mongoose.Schema({ text: String, completed: Boolean });   exports.get = function (request, response) {     mongoose.connect('<your Mongo connection string> ');     TodoItemModel = mongoose.model('todoitem', schema);     TodoItemModel.find(function (err, items) {         if (err) {             console.log('error:' + err);             return response.send(500);         }         response.send(200, items);     }); }; Don’t forget to push your changes to your mobile service once you are done > git add . > git commit –m "Switched to use Mongo Labs" > git push Now our Mobile Service app is using Mongo DB! Note, with today’s update usage of custom Node.js modules is limited to Custom API scripts only. We will enable it in all scripts (including data and custom CRON tasks) shortly. New Mobile Services NuGet package, including .NET 4.5 support A few months ago we announced a new pre-release version of the Mobile Services client SDK based on portable class libraries (PCL). Today, we are excited to announce that this new library is now a stable .NET client SDK for mobile services and is no longer a pre-release package. Today’s update includes full support for Windows Store, Windows Phone 7.x, and .NET 4.5, which allows developers to use Mobile Services from ASP.NET or WPF applications. You can install and use this package today via NuGet. Mobile Services and Web Sites: Free 20MB Database for Mobile Services and Web Sites Starting today, every customer of Windows Azure gets one Free 20MB database to use for 12 months free (for both dev/test and production) with Web Sites and Mobile Services. When creating a Mobile Service or a Web Site, simply chose the new “Create a new Free 20MB database” option to take advantage of it: You can use this free SQL Database together with the 10 free Web Sites and 10 free Mobile Services you get with your Windows Azure subscription, or from any other Windows Azure VM or Cloud Service. Notification Hubs: Android Broadcast Push Notification Support Earlier this year, we introduced a new capability in Windows Azure for sending broadcast push notifications at high scale: Notification Hubs. In the initial preview of Notification Hubs you could use this support with both iOS and Windows devices.  Today we’re excited to announce new Notification Hubs support for sending push notifications to Android devices as well. Push notifications are a vital component of mobile applications.  They are critical not only in consumer apps, where they are used to increase app engagement and usage, but also in enterprise apps where up-to-date information increases employee responsiveness to business events.  You can use Notification Hubs to send push notifications to devices from any type of app (a Mobile Service, Web Site, Cloud Service or Virtual Machine). Notification Hubs provide you with the following capabilities: Cross-platform Push Notifications Support. Notification Hubs provide a common API to send push notifications to iOS, Android, or Windows Store at once.  Your app can send notifications in platform specific formats or in a platform-independent way.  Efficient Multicast. Notification Hubs are optimized to enable push notification broadcast to thousands or millions of devices with low latency.  Your server back-end can fire one message into a Notification Hub, and millions of push notifications can automatically be delivered to your users.  Devices and apps can specify a number of per-user tags when registering with a Notification Hub. These tags do not need to be pre-provisioned or disposed, and provide a very easy way to send filtered notifications to an infinite number of users/devices with a single API call.   Extreme Scale. Notification Hubs enable you to reach millions of devices without you having to re-architect or shard your application.  The pub/sub routing mechanism allows you to broadcast notifications in a super-efficient way.  This makes it incredibly easy to route and deliver notification messages to millions of users without having to build your own routing infrastructure. Usable from any Backend App. Notification Hubs can be easily integrated into any back-end server app, whether it is a Mobile Service, a Web Site, a Cloud Service or an IAAS VM. It is easy to configure Notification Hubs to send push notifications to Android. Create a new Notification Hub within the Windows Azure Management Portal (New->App Services->Service Bus->Notification Hub): Then register for Google Cloud Messaging using https://code.google.com/apis/console and obtain your API key, then simply paste that key on the Configure tab of your Notification Hub management page under the Google Cloud Messaging Settings: Then just add code to the OnCreate method of your Android app’s MainActivity class to register the device with Notification Hubs: gcm = GoogleCloudMessaging.getInstance(this); String connectionString = "<your listen access connection string>"; hub = new NotificationHub("<your notification hub name>", connectionString, this); String regid = gcm.register(SENDER_ID); hub.register(regid, "myTag"); Now you can broadcast notification from your .NET backend (or Node, Java, or PHP) to any Windows Store, Android, or iOS device registered for “myTag” tag via a single API call (you can literally broadcast messages to millions of clients you have registered with just one API call): var hubClient = NotificationHubClient.CreateClientFromConnectionString(                   “<your connection string with full access>”,                   "<your notification hub name>"); hubClient.SendGcmNativeNotification("{ 'data' : {'msg' : 'Hello from Windows Azure!' } }", "myTag”); Notification Hubs provide an extremely scalable, cross-platform, push notification infrastructure that enables you to efficiently route push notification messages to millions of mobile users and devices.  It will make enabling your push notification logic significantly simpler and more scalable, and allow you to build even better apps with it. Learn more about Notification Hubs here on MSDN . Summary The above features are now live and available to start using immediately (note: some of the services are still in preview).  If you don’t already have a Windows Azure account, you can sign-up for a free trial and start using them today.  Visit the Windows Azure Developer Center to learn more about how to build apps with it. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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• How can an SQL relational database be used to model a thesaurus? [closed]

  - by Miles O'Keefe

  I would like to design a web app that functions as a simple thesaurus: a long list of words with attributes, all of which are linked to each other. This thesaurus data model can be defined as: a controlled vocabulary arranged in a known order in which equivalence, hierarchical, and associative relationships among terms are clearly displayed and identified by standardized relationship indicators. My idea so far is to have one database in which every word is a table, and every table contains all words related to that word. e.g. Thesaurus(database) - happy(table) - excited(row)|cheerful(row)|lively(row) Is there are more efficient way to store words and their relationship to other words in a relational SQL database?

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• Optimistic non-locking copy of InnoDB .frm files

  - by jothir

  MySQL Enterprise Backup(MEB) does hot backup of innodb data and log files. Till MEB 3.6.1, the user backs up the only innodb tables in a 3 step process: STEP 1. Take backup using --only-innodb option STEP 2. Temporarily make the table read only by executing “FLUSH TABLES WITH READ LOCK” MEB 3.7.0 has an enhancement to innodb file copying. The .frm files gets copied along with the hot backup done for innodb files. I would like to make the blog a little interactive by explaining the feature as answers: 1. What are these .frm files? The files containing the metadata, such as the table definition, of a MySQL table. For backups, the full set of .frm files are always required along with the backup data, to be able to restore tables that are altered or dropped after the backup. 2. Can the .frm files not be copied by MEB itself? --only-innodb-with-frm is the new option introduced in MEB 3.7.1 to do a copy of .frm files without locking the tables during backup operation itself. This is to reduce the pain of manually copying the .frm files. The option is intended for backups where you can ensure that no ALTER TABLE, CREATE TABLE, DROP TABLE, or other DDL statements modify the .frm files for InnoDB tables during the backup operation. 3. How is data consistency ensured? MEB does validation of the .frm files after copying by comparing with the server directory to see if the timestamps of any of the .frm files is greater than the saved system time (check .frm time).  This change in timestamp of the .frm files will show if a table is altered during the process of backup. The total number of frm files in the server directory is also verified against the copied contents. If the number of .frm files is less compared to server directory, it shows that table/tables have been dropped during the process of backup. If the number of .frm files is more compared to server directory, it shows that new table/tables have been created during backup operation. 4. How does MEB handle data inconsistency? MEB copies the .frm files through several iterations,  does the validation and throws a WARNING if there is any inconsistency found in .frm files at the end of backup operation. This means the user is warned of some DDL operations that had occurred during backup operation, and has to manually copy the .frm files or do a backup again. 5. What is the option and explain its usage? The option introduced is --only-innodb-with-frm which does optimistic copy of .frm files without locking. This can be used when the user wants to backup only innodb tables along with .frm files. The option can take one of the 2 values: all | related. --only-innodb-with-frm=all does copy of all .frm files of all innodb tables. --only-innodb-with-frm=related works in conjunction with --include option.This is to allow partial backup of .frm files corresponding to the tables specified in --include. Let me show the usage with example output: ./mysqlbackup -uroot --backup-dir=/logs/backupWithFrmAll --only-innodb-with-frm=all backup MySQL Enterprise Backup version 3.7.1 [2012/06/05] Copyright (c) 2003, 2012, Oracle and/or its affiliates. All Rights Reserved. INFO: Starting with following command line ... ./mysqlbackup -uroot --backup-dir=/logs/backupWithFrmAll        --only-innodb-with-frm=all backup INFO: Got some server configuration information from running server. IMPORTANT: Please check that mysqlbackup run completes successfully.            At the end of a successful 'backup' run mysqlbackup            prints "mysqlbackup completed OK!". --------------------------------------------------------------------                       Server Repository Options: --------------------------------------------------------------------  datadir                          =  /mysql/trydb/  innodb_data_home_dir             =    innodb_data_file_path            =  ibdata1:10M:autoextend  innodb_log_group_home_dir        =  /mysql/trydb/  innodb_log_files_in_group        =  2  innodb_log_file_size             =  5242880 --------------------------------------------------------------------                       Backup Config Options: --------------------------------------------------------------------  datadir                          =  /logs/backupWithFrmAll/datadir  innodb_data_home_dir             =  /logs/backupWithFrmAll/datadir  innodb_data_file_path            =  ibdata1:10M:autoextend  innodb_log_group_home_dir        =  /logs/backupWithFrmAll/datadir  innodb_log_files_in_group        =  2  innodb_log_file_size             =  5242880 mysqlbackup: INFO: Unique generated backup id for this is 13451979804504860 mysqlbackup: INFO: Uses posix_fadvise() for performance optimization. mysqlbackup: INFO: System tablespace file format is Antelope. mysqlbackup: INFO: Found checkpoint at lsn 1656792. mysqlbackup: INFO: Starting log scan from lsn 1656320. 120817 15:36:22 mysqlbackup: INFO: Copying log... 120817 15:36:22 mysqlbackup: INFO: Log copied, lsn 1656792.          We wait 1 second before starting copying the data files... 120817 15:36:23 mysqlbackup: INFO: Copying /mysql/trydb/ibdata1 (Antelope file format). 120817 15:36:23 mysqlbackup: INFO: Copying /mysql/trydb/innodb1/table2.ibd (Antelope file format). 120817 15:36:23 mysqlbackup: INFO: Copying /mysql/trydb/innodb1/table3.ibd (Antelope file format). 120817 15:36:23 mysqlbackup: INFO: Copying /mysql/trydb/innodb1/table1.ibd (Antelope file format). mysqlbackup: INFO: Opening backup source directory '/mysql/trydb/' 120817 15:36:23 mysqlbackup: INFO: Starting to backup .frm files in the subdirectories of /mysql/trydb/ mysqlbackup: INFO: Copying innodb data and logs during final stage ... mysqlbackup: INFO: A copied database page was modified at 1656792.          (This is the highest lsn found on page)          Scanned log up to lsn 1656792.          Was able to parse the log up to lsn 1656792.          Maximum page number for a log record 0 mysqlbackup: INFO: Copying non-innodb files took 2.000 seconds 120817 15:36:25 mysqlbackup: INFO: Full backup completed! mysqlbackup: INFO: Backup created in directory '/logs/backupWithFrmAll' -------------------------------------------------------------   Parameters Summary          -------------------------------------------------------------   Start LSN                  : 1656320   End LSN                    : 1656792 ------------------------------------------------------------- mysqlbackup completed OK! bash$ ls /logs/backupWithFrmAll/datadir/innodb1/ table1.frm  table1.ibd  table2.frm  table2.ibd  table3.frm  table3.ibd Here the backup directory contains all the .frm files of all the innodb tables. ./mysqlbackup -uroot --backup-dir=/logs/backupWithFrm --include="innodb1.table3.*" --only-innodb-with-frm=related backup MySQL Enterprise Backup version 3.7.1 [2012/06/05] Copyright (c) 2003, 2012, Oracle and/or its affiliates. All Rights Reserved. INFO: Starting with following command line ... ./mysqlbackup -uroot --backup-dir=/logs/backup371frm        --include=innodb1.table3.* --only-innodb-with-frm=related backup INFO: Got some server configuration information from running server. IMPORTANT: Please check that mysqlbackup run completes successfully.            At the end of a successful 'backup' run mysqlbackup            prints "mysqlbackup completed OK!". --------------------------------------------------------------------                       Server Repository Options: --------------------------------------------------------------------  datadir                          = /mysql/trydb/  innodb_data_home_dir             =    innodb_data_file_path            =  ibdata1:10M:autoextend  innodb_log_group_home_dir        =  /mysql/trydb  innodb_log_files_in_group        =  2  innodb_log_file_size             =  5242880 --------------------------------------------------------------------                       Backup Config Options: --------------------------------------------------------------------  datadir                          =  /logs/backupWithFrm/datadir  innodb_data_home_dir             =  /logs/backupWithFrm/datadir  innodb_data_file_path            =  ibdata1:10M:autoextend  innodb_log_group_home_dir        =  /logs/backupWithFrm/datadir  innodb_log_files_in_group        =  2  innodb_log_file_size             =  5242880 mysqlbackup: INFO: Unique generated backup id for this is 13451973458118162 mysqlbackup: INFO: Uses posix_fadvise() for performance optimization. mysqlbackup: INFO: The --include option specified: innodb1.table3.* mysqlbackup: INFO: System tablespace file format is Antelope. mysqlbackup: INFO: Found checkpoint at lsn 1656792. mysqlbackup: INFO: Starting log scan from lsn 1656320. 120817 15:25:47 mysqlbackup: INFO: Copying log... 120817 15:25:47 mysqlbackup: INFO: Log copied, lsn 1656792.          We wait 1 second before starting copying the data files... 120817 15:25:48 mysqlbackup: INFO: Copying /mysql/trydbibdata1 (Antelope file format). 120817 15:25:49 mysqlbackup: INFO: Copying /mysql/trydbinnodb1/table3.ibd (Antelope file format). mysqlbackup: INFO: Opening backup source directory '/mysql/trydb' 120817 15:25:49 mysqlbackup: INFO: Starting to backup .frm files in the subdirectories of /mysql/trydb mysqlbackup: INFO: Copying innodb data and logs during final stage ... mysqlbackup: INFO: A copied database page was modified at 1656792.          (This is the highest lsn found on page)          Scanned log up to lsn 1656792.          Was able to parse the log up to lsn 1656792.          Maximum page number for a log record 0 mysqlbackup: INFO: Copying non-innodb files took 2.000 seconds 120817 15:25:51 mysqlbackup: INFO: Full backup completed! mysqlbackup: INFO: Backup created in directory '/logs/backupWithFrm' -------------------------------------------------------------   Parameters Summary          -------------------------------------------------------------   Start LSN                  : 1656320   End LSN                    : 1656792 ------------------------------------------------------------- mysqlbackup completed OK! bash$ ls /logs/backupWithFrm/datadir/innodb1/ table3.frm table3.ibd Thus the backup directory contains only the .frm file matching the innodb table name specified in --include option. In a nutshell, we present our great new option --only-innodb-with-frm which is a true hot InnoDB-only backup with .frm files, but with an additional check, if any DDL happened during the backup. If a DDL has happened, the DBA can decide if to repeat the backup, or to live with the potential inconsistency. This is the ideal solution for users that have all their "real" data in InnoDB and seldom change their schemas. You may also like: http://dev.mysql.com/doc/mysql-enterprise-backup/3.7/en/backup-partial-options.html   STEP 3. Manually copy the .frm files of innodb tables to the destination directory where backup is stored.

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• Android Bitmap : collision Detecting [on hold]

  - by user2505374

  I am writing an Android game right now and I would need some help in the collision of the wall on screen. When I drag the ball in the top and right it able to collide in wall but when I drag it faster it was able to overlap in the wall. public boolean onTouchEvent(MotionEvent event) { int x = (int) event.getX(); int y = (int) event.getY(); switch (event.getAction()) { // if the player moves case MotionEvent.ACTION_MOVE: { if (playerTouchRect.contains(x, y)) { boolean left = false; boolean right = false; boolean up = false; boolean down = false; boolean canMove = false; boolean foundFinish = false; if (x != pLastXPos) { if (x < pLastXPos) { left = true; } else { right = true; } pLastXPos = x; } if (y != pLastYPos) { if (y < pLastYPos) { up = true; } else { down = true; } pLastYPos = y; } plCellRect = getRectFromPos(x, y); newplRect.set(playerRect); newplRect.left = x - (int) (playerRect.width() / 2); newplRect.right = x + (int) (playerRect.width() / 2); newplRect.top = y - (int) (playerRect.height() / 2); newplRect.bottom = y + (int) (playerRect.height() / 2); int currentRow = 0; int currentCol = 0; currentRow = getRowFromYPos(newplRect.top); currentCol = getColFromXPos(newplRect.right); if(!canMove){ canMove = mapManager.getCurrentTile().pMaze[currentRow][currentCol] == Cell.wall; canMove =true; } finishTest = mapManager.getCurrentTile().pMaze[currentRow][currentCol]; foundA = finishTest == Cell.valueOf(letterNotGet + ""); canMove = mapManager.getCurrentTile().pMaze[currentRow][currentCol] != Cell.wall; canMove = (finishTest == Cell.floor || finishTest == Cell.pl) && canMove; if (canMove) { invalidate(); setTitle(); } if (foundA) { mapManager.getCurrentTile().pMaze[currentRow][currentCol] = Cell.floor; // finishTest letterGotten.add(letterNotGet); playCurrentLetter(); /*sounds.play(sExplosion, 1.0f, 1.0f, 0, 0, 1.5f);*/ foundS = letterNotGet == 's'; letterNotGet++; }if(foundS){ AlertDialog.Builder builder = new AlertDialog.Builder(mainActivity); builder.setTitle(mainActivity.getText(R.string.finished_title)); LayoutInflater inflater = mainActivity.getLayoutInflater(); View view = inflater.inflate(R.layout.finish, null); builder.setView(view); View closeButton =view.findViewById(R.id.closeGame); closeButton.setOnClickListener(new OnClickListener() { @Override public void onClick(View clicked) { if(clicked.getId() == R.id.closeGame) { mainActivity.finish(); } } }); AlertDialog finishDialog = builder.create(); finishDialog.show(); } else { Log.d(TAG, "INFO: updated player position"); playerRect.set(newplRect); setTouchZone(); updatePlayerCell(); } } // end of (CASE) if playerTouch break; } // end of (SWITCH) Case motion }//end of Switch return true; }//end of TouchEvent private void finish() { // TODO Auto-generated method stub } public int getColFromXPos(int xPos) { val = xPos / (pvWidth / mapManager.getCurrentTile().pCols); if (val == mapManager.getCurrentTile().pCols) { val = mapManager.getCurrentTile().pCols - 1; } return val; } /** * Given a y pixel position, return the row of the cell it is in This is * used when determining the type of adjacent Cells. * * @param yPos * y position in pixels * @return The cell this position is in */ public int getRowFromYPos(int yPos) { val = yPos / (pvHeight / mapManager.getCurrentTile().pRows); if (val == mapManager.getCurrentTile().pRows) { val = mapManager.getCurrentTile().pRows - 1; } return val; } /** * When preserving the position we need to know which cell the player is in, * so calculate it from the centre on its Rect */ public void updatePlayerCell() { plCell.x = (playerRect.left + (playerRect.width() / 2)) / (pvWidth / mapManager.getCurrentTile().pCols); plCell.y = (playerRect.top + (playerRect.height() / 2)) / (pvHeight / mapManager.getCurrentTile().pRows); if (mapManager.getCurrentTile().pMaze[plCell.y][plCell.x] == Cell.floor) { for (int row = 0; row < mapManager.getCurrentTile().pRows; row++) { for (int col = 0; col < mapManager.getCurrentTile().pCols; col++) { if (mapManager.getCurrentTile().pMaze[row][col] == Cell.pl) { mapManager.getCurrentTile().pMaze[row][col] = Cell.floor; break; } } } mapManager.getCurrentTile().pMaze[plCell.y][plCell.x] = Cell.pl; } } public Rect getRectFromPos(int x, int y) { calcCell.left = ((x / cellWidth) + 0) * cellWidth; calcCell.right = calcCell.left + cellWidth; calcCell.top = ((y / cellHeight) + 0) * cellHeight; calcCell.bottom = calcCell.top + cellHeight; Log.d(TAG, "Rect: " + calcCell + " Player: " + playerRect); return calcCell; } public void setPlayerRect(Rect newplRect) { playerRect.set(newplRect); } private void setTouchZone() { playerTouchRect.set( playerRect.left - playerRect.width() / TOUCH_ZONE, playerRect.top - playerRect.height() / TOUCH_ZONE, playerRect.right + playerRect.width() / TOUCH_ZONE, playerRect.bottom + playerRect.height() / TOUCH_ZONE); } public Rect getPlayerRect() { return playerRect; } public Point getPlayerCell() { return plCell; } public void setPlayerCell(Point cell) { plCell = cell; }

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• Why is this 8 puzzle unsolvable?

  - by Ashwin

  I am developing a 8 puzzle game. I went through the rules in this (see Detecting Unsolvable Puzzles) link, which tell you how to detect if an initial state is unsolvable. It says that if the number of inversions is odd, then the goal state cannot be reached and if even the goal state can be reached. Inversion is defined as Given a board, an inversion is any pair of blocks i and j where i < j but i appears after j when considering the board in row-major order (row 0, followed by row 1, and so forth). There is a 8-puzzle solver(applet) here. Choose 8-puzzle from the options. 1,0,3,2,4,5,6,7,8 and 7,0,2,8,5,3,6,4,1 As you can see both of them contain an even number of inversions. Still the program says that the puzzle is unsolvable. So is the Princeton link wrong?

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• 12c - Invisible Columns...

  - by noreply(at)blogger.com (Thomas Kyte)

  Remember when 11g first came out and we had "invisible indexes"?  It seemed like a confusing feature - indexes that would be maintained by modifications (hence slowing them down), but would not be used by queries (hence never speeding them up).  But - after you looked at them a while, you could see how they can be useful.  For example - to add an index in a running production system, an index used by the next version of the code to be introduced later that week - but not tested against the queries in version one of the application in place now.  We all know that when you add an index - one of three things can happen - a given query will go much faster, it won't affect a given query at all, or... It will make some untested query go much much slower than it used to.  So - invisible indexes allowed us to modify the schema in a 'safe' manner - hiding the change until we were ready for it.Invisible columns accomplish the same thing - the ability to introduce a change while minimizing any negative side effects of that change.  Normally when you add a column to a table - any program with a SELECT * would start seeing that column, and programs with an INSERT INTO T VALUES (...) would pretty much immediately break (an INSERT without a list of columns in it).  Now we can add a column to a table in an invisible fashion, the column will not show up in a DESCRIBE command in SQL*Plus, it will not be returned with a SELECT *, it will not be considered in an INSERT INTO T VALUES statement.  It can be accessed by any query that asks for it, it can be populated by an INSERT statement that references it, but you won't see it otherwise.For example, let's start with a simple two column table:ops$tkyte%ORA12CR1> create table t  2  ( x int,  3    y int  4  )  5  /Table created.ops$tkyte%ORA12CR1> insert into t values ( 1, 2 );1 row created.Now, we will add an invisible column to it:ops$tkyte%ORA12CR1> alter table t add                     ( z int INVISIBLE );Table altered.Notice that a DESCRIBE will not show us this column:ops$tkyte%ORA12CR1> desc t Name              Null?    Type ----------------- -------- ------------ X                          NUMBER(38) Y                          NUMBER(38)and existing inserts are unaffected by it:ops$tkyte%ORA12CR1> insert into t values ( 3, 4 );1 row created.A SELECT * won't see it either:ops$tkyte%ORA12CR1> select * from t;         X          Y---------- ----------         1          2         3          4But we have full access to it (in well written programs! The ones that use a column list in the insert and select - never relying on "defaults":ops$tkyte%ORA12CR1> insert into t (x,y,z)                         values ( 5,6,7 );1 row created.ops$tkyte%ORA12CR1> select x, y, z from t;         X          Y          Z---------- ---------- ----------         1          2         3          4         5          6          7and when we are sure that we are ready to go with this column, we can just modify it:ops$tkyte%ORA12CR1> alter table t modify z visible;Table altered.ops$tkyte%ORA12CR1> select * from t;         X          Y          Z---------- ---------- ----------         1          2         3          4         5          6          7I will say that a better approach to this - one that is available in 11gR2 and above - would be to use editioning views (part of Edition Based Redefinition - EBR ).  I would rather use EBR over this approach, but in an environment where EBR is not being used, or the editioning views are not in place, this will achieve much the same.Read these for information on EBR:http://www.oracle.com/technetwork/issue-archive/2010/10-jan/o10asktom-172777.htmlhttp://www.oracle.com/technetwork/issue-archive/2010/10-mar/o20asktom-098897.htmlhttp://www.oracle.com/technetwork/issue-archive/2010/10-may/o30asktom-082672.html

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• How can I support scrolling when using batched rendering for my tiles?

  - by dardanel

  I have tiled map 100*75 and tiles are 32*32 pixel.I want to use batching for performance .I don't figure it out , because of my game needs scrolling and every frame i draw 22*16 tiles (my screen is 20*16 tile) .I thought that batching tiles for every frame .Is it good or any suggestion? edit :to more clarify I want to use occlusion culling and batching at the same time.I thought that drawing only visible areas and batching them together .But there is a something i couldn't figure out .When scrolling screen with translate matrix , if one row become invisible , I bind new row and batch them again.Every batched objects needs to buffer again.So I batch tiles and buffer to VBO every time when one row become invisible .I don't know these way is efficient or not .This is my question .And i am open to any suggestions.

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