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  • T-SQL SQL Server - Stored Procedure with parameter

    - by Ricardo Conte
    Please, the first TSQL works FINE, the second does not. I guess it must be a simple mistake, since I am not used to T-SQL. Thank you for the answers. R Conte. * WORKS FINE ******************* (parm hard-coded) ALTER PROCEDURE rconte.spPesquisasPorStatus AS SET NOCOUNT ON SELECT pesId, RTRIM(pesNome), pesStatus, pesPesGrupoRespondente, pesPesQuestionario, pesDataPrevistaDisponivel, pesDataPrevistaEncerramento, pesDono FROM dbo.tblPesquisas WHERE (pesStatus = 'dis') ORDER BY pesId DESC RETURN Running [rconte].[spPesquisasPorStatus]. pesId Column1 pesStatus pesPesGrupoRespondente pesPesQuestionario pesDataPrevistaDisponivel pesDataPrevistaEncerramento pesDono 29 XXXXXXXXX xxxxx dis 17 28 5/5/2010 08:21:12 5/5/2010 08:21:12 1 28 Xxxxxxxx xxxxxxxxxxxxx dis 16 27 5/5/2010 07:44:12 5/5/2010 07:44:12 1 27 Xxxxxxxxxxxxxxxxxxxxxxx * DOES NOT WORK ************** (using a parm; pesStatus is nchar(3)) ALTER PROCEDURE rconte.spPesquisasPorStatus (@pPesStatus nchar(3) = 'dis') AS SET NOCOUNT ON SELECT pesId, RTRIM(pesNome), pesStatus, pesPesGrupoRespondente, pesPesQuestionario, pesDataPrevistaDisponivel, pesDataPrevistaEncerramento, pesDono FROM dbo.tblPesquisas WHERE (pesStatus = @pPesStatus) ORDER BY pesId DESC RETURN Running [rconte].[spPesquisasPorStatus] ( @pPesStatus = 'dis' ). pesId Column1 pesStatus pesPesGrupoRespondente pesPesQuestionario pesDataPrevistaDisponivel pesDataPrevistaEncerramento pesDono No rows affected. (0 row(s) returned) @RETURN_VALUE = 0 Finished running [rconte].[spPesquisasPorStatus]

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  • How to write a SQL query for numerous conditions with lots of fields in ASP.NET

    - by Yongwei Xing
    Hi all I have a ASP.NET site. There is a table in the SQL Server with more than 30 fields. I need make a page on which there are many filters to query data from database based on the filters you select or input. One filter for one fields in the database. The filter would be dropdown list, textbox,checkbox or listbox. If you do not choose one filter, it means select all for this field. So there are lots of combination for these fields. Is there any simple way to write such page and query for this requirement? Best Regards,

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  • JDBC CommunicationsException with MySQL Database

    - by Dominik Siebel
    I'm having a little trouble with my MySQL- Connection- Pooling. This is the case: Different jobs are scheduled via Quartz. All jobs connect to different databases which works fine the whole day while the nightly scheduled jobs fail with a CommunicationsException... Quartz-Jobs: Job1 runs 0 0 6,10,14,18 * * ? Job2 runs 0 30 10,18 * * ? Job3 runs 0 0 5 * * ? As you can see the last job runs at 18 taking about 1 hour to run. The first job at 5am is the one that fails. I already tried all kinds of parameter-combinations in my resource config this is the one I am running right now: <!-- Database 1 (MySQL) --> <Resource auth="Container" driverClassName="com.mysql.jdbc.Driver" maxActive="100" maxIdle="30" maxWait="10000" removeAbandoned="true" removeAbandonedTimeout="60" logAbandoned="true" type="javax.sql.DataSource" name="jdbc/appDbProd" username="****" password="****" url="jdbc:mysql://127.0.0.1:3306/appDbProd?autoReconnect=true&amp;useUnicode=true&amp;characterEncoding=UTF-8" testWhileIdle="true" testOnBorrow="true" testOnReturn="true" validationQuery="SELECT 1" timeBetweenEvictionRunsMillis="1800000" /> <!-- Database 2 (MySQL) --> <Resource auth="Container" driverClassName="com.mysql.jdbc.Driver" maxActive="100" maxIdle="30" maxWait="10000" removeAbandoned="true" removeAbandonedTimeout="60" logAbandoned="true" type="javax.sql.DataSource" name="jdbc/prodDbCopy" username="****" password="****" url="jdbc:mysql://127.0.0.1:3306/prodDbCopy?autoReconnect=true&amp;useUnicode=true&amp;characterEncoding=UTF-8" testWhileIdle="true" testOnBorrow="true" testOnReturn="true" validationQuery="SELECT 1" timeBetweenEvictionRunsMillis="1800000" /> <!-- Database 3 (MSSQL)--> <Resource auth="Container" driverClassName="net.sourceforge.jtds.jdbc.Driver" maxActive="30" maxIdle="30" maxWait="100" removeAbandoned="true" removeAbandonedTimeout="60" logAbandoned="true" name="jdbc/catalogDb" username="****" password="****" type="javax.sql.DataSource" url="jdbc:jtds:sqlserver://127.0.0.1:1433;databaseName=catalog;useNdTLMv2=false" testWhileIdle="true" testOnBorrow="true" testOnReturn="true" validationQuery="SELECT 1" timeBetweenEvictionRunsMillis="1800000" /> For obvious reasons I changed IPs, Usernames and Passwords but they can be assumed to be correct, seeing that the application runs successfully the whole day. The most annoying thing is: The first job that runs first queries Database2 successfully but fails to query Database1 for some reason (CommunicationsException): Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 39,376,539 milliseconds ago. The last packet sent successfully to the server was 39,376,539 milliseconds ago. is longer than the server configured value of 'wait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem. Any ideas? Thanks!

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  • WHERE clause confusion with PDO

    - by Greg
    I'm having some trouble understanding how to use prepared statements, when you need to match one value against several columns at once. In other words what instead of doing this: $stmt = $dbh-prepare("SELECT * FROM REGISTRY where name = ?"); $stmt-bindParam(':name', $name); I wanted to do this: $stmt = $dbh-prepare("SELECT * FROM REGISTRY where firstname = ? or lastname = ?"); with both '?' representing the same string.

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  • Stop a postback in javascript

    - by jmpena
    hello, i have an ASP webform with a JQuery Thickbox, i have an image that opens the thickbox when user click. once open the thickbox it shows me a grid with several rows and a button to select one and after the user select the record it returns to the main page the recordselected and cause a __doPostBack() BUT! sometimes in IE6 it stay loading the postback and never ends i have to refresh the page and when it refresh it shows everything fine. but i dont want the postback stay loading AND it does not happend always. i have to call a __doPostBack because i need to find info related to the selected record. thanks.

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  • Get latest sql rows based on latest date and per user

    - by Umair
    I have the following table: RowId, UserId, Date 1, 1, 1/1/01 2, 1, 2/1/01 3, 2, 5/1/01 4, 1, 3/1/01 5, 2, 9/1/01 I want to get the latest records based on date and per UserId but as a part of the following query (due to a reason I cannot change this query as this is auto generated by a tool but I can write pass any thing starting with AND...): SELECT RowId, UserId, Date FROM MyTable WHERE 1 = 1 AND ( // everything which needs to be done goes here . . . ) I have tried similar query, but get an error: Only one expression can be specified in the select list when the subquery is not introduced with EXISTS.

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  • Checking if MySQL Database data does not exist

    - by Ben Sinclair
    I have my songs set-up in my MySQL database. Each song is is either assigned multiple locations or has no locations at all. Only the songs that either have no locations assigned in the database or have the location assigned to the ones specified below should be pulled from the database. Hopefully when you understand my query below it will make sense SELECT s.* FROM roster_songs AS s LEFT JOIN roster_songs_locations AS sl ON sl.song_id = s.id WHERE EXISTS ( SELECT sl2.* FROM roster_songs_locations AS sl2 WHERE s.id != sl2.song_id ) OR ( sl.location_id = '88fb5f94-aaa6-102c-a4fa-1f05bca0eec6' OR sl.location_id = '930555b0-a251-102c-a245-1559817ce81a' ) GROUP BY s.id The query almost works except it pulls out of the database songs that are assigned to sl.location_id's that aren't specified in the above query. I think it has something to do with my EXISTS code picking them up... Any ideas how I can get this to work?

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  • Set a dropdown option to selected based on get variable in url in Razor MVC

    - by Mason240
    I have a dropdown menu in a GET form. When the user hits submit, they are directed to the same page and shown the form again. I would like to have the dropdown option the user displayed in the last page already selected. So for example: @Html.DropDownList("Type", null, "Type", new { @class = "sbox-input" } ) website.com/Search?Type="Beef" <select name="Type"> <option value="Fish" >Fish</option> <option value="Chicken" >Chicken</option> <option value="Beef" selected="selected">Beef</option> </select> A jQuery solution would work just as well.

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  • DBLinq not generating where clause

    - by sipwiz
    I'm testing out DBLinq-0.18 and DBLinq from SVN Trunk with MySQL and Postgresql. I'm only using a very simple query but on both database DBLinq is not generating a Where clause. I have confirmed this by turning on statement logging on Postgresql to check exactly what request DBLinq is sending. My Linq query is: MyDB db = new MyDB(new NpgsqlConnection("Database=database;Host=localhost;User Id=postgres;Password=password")); var customers = from customer in db.Customers where customer.CustomerUserName == "test" select customer; The query works ok but the SQL generated by DBLinq is of the form: select customerusername, customerpassword .... from public.customers There is no Where clause which means DBLinq must be pulling the whole table down before running the Linq query. Has anyone had any experience with DBLinq and know what I could be doing wrong?

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  • What are the types and inner workings of a query optimizer?

    - by Frank Developer
    As I understand it, most query optimizers are cost-based. Some can be influenced by hints like FIRST_ROWS(). Others are tailored for OLAP. Is it possible to know more detailed logic about how Informix IDS and SE's optimizers decide what's the best route for processing a query, other than SET EXPLAIN? Is there any documentation which illustrates the ranking of SELECT statements? I would imagine that "SELECT col FROM table WHERE ROWID = n" ranks 1st. What are the rest of them?.. If I'm not mistaking, Informix's ROWID is a SERIAL(INT) which allows for a max. of 2GB nrows, or maybe it uses INT9 for TB's nrows?.. However, I think Oracle uses HEX values for ROWID. Too bad ROWID can't be oftenly used, since a rows ROWID can change. So maybe ROWID is used by the optimizer as a counter? Perhaps, it could be used for implementing the query progress idea I mentioned in my "Begin viewing query results before query completes" question? For some reason, I feel it wouldn't be that difficult to report a query's progress while being processed, perhaps at the expense of some slight overhead, but it would be nice to know ahead of time: A "Google-like" estimate of how many rows meet a query's criteria, display it's progress every 100, 200, 500 or 1,000 rows, give users the ability to cancel it at anytime and start displaying the qualifying rows as they are being put into the current list, while it continues searching?.. This is just one example, perhaps we could think other neat/useful features, the ingridients are more or less there. Perhaps we could fine-tune each query with more granularity than currently available? OLTP queries tend to be mostly static and pre-defined. The "what-if's" are more OLAP, so let's try to add more control and intelligence to it? So, therefore, being able to more precisely control, not "hint-influence" a query is what's needed and therefore it would be necessary to know how the optimizers logic is programmed. We can then have Dynamic SELECT and other statements for specific situations! Maybe even tell IDS to read blocks of indexes nodes at-a-time instead of one-by-one, etc. etc.

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  • How to implement filter system in SQL?

    - by sadvaw
    Right now I am planning to add a filter system to my site. Examples: (ID=apple, COLOR=red, TASTE=sweet, ORIGIN=US) (ID=mango, COLOR=yellow, TASTE=sweet, ORIGIN=MEXICO) (ID=banana, COLOR=yellow, TASTE=bitter-sweet, ORIGIN=US) so now I am interested in doing the following: SELECT ID FROM thisTable WHERE COLOR='yellow' AND TASTE='SWEET' But my problem is I am doing this for multiple categories in my site, and the columns are NOT consistent. (like if the table is for handphones, then it will be BRAND, 3G-ENABLED, PRICE, COLOR, WAVELENGTH, etc) how could I design a general schema that allows this? Right now I am planning on doing: table(ID, KEY, VALUE) This allows arbitary number of columns, but for the query, I am using SELECT ID FROM table WHERE (KEY=X1 AND VALUE=V1) AND (KEY=X2 AND VALUE=V2), .. which returns an empty set. Can someone recommend a good solution to this? Note that the number of columns WILL change regularly

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  • Aggregate Functions on subsets of data based on current row values with SQL

    - by aasukisuki
    Hopefully that title makes sense... Let's say I have an employee table: ID | Name | Title | Salary ---------------------------- 1 | Bob | Manager | 15285 2 | Joe | Worker | 10250 3 | Al | Worker | 11050 4 | Paul | Manager | 16025 5 | John | Worker | 10450 What I'd like to do is write a query that will give me the above table, along with an averaged salary column, based on the employee title: ID | Name | Title | Salary | Pos Avg -------------------------------------- 1 | Bob | Manager | 15285 | 15655 2 | Joe | Worker | 10250 | 10583 3 | Al | Worker | 11050 | 10583 4 | Paul | Manager | 16025 | 15655 5 | John | Worker | 10450 | 10583 I've tried doing this with a sub-query along the lines of: Select *, (select Avg(e2.salary) from employee e2 where e2.title = e.title) from employee e But I've come to realize that the sub-query is executed first, and has no knowledge of the table alias'd e I'm sure I'm missing something REALLY obvious here, can anyone point me in the right diretion?

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  • JPA optimistic lock - setting @Version to entity class cause query to include VERSION as column

    - by masato-san
    I'm using JPA Toplink Essential, Netbean6.8, GlassFish v3 In my Entity class I added @Version annotation to enable optimistic locking at transaction commit however after I added the annotation, my query started including VERSION as column thus throwing SQL exception. None of this is mentioned in any tutorial I've seen so far. What could be wrong? Snippet public class MasatosanTest2 implements Serializable { private static final long serialVersionUID = 1L; @Id @Basic(optional = false) @Column(name = "id") private Integer id; @Column(name = "username") private String username; @Column(name = "note") private String note; //here adding Version @Version int version; query used: SELECT m FROM MasatosanTest2 m Internal Exception: com.microsoft.sqlserver.jdbc.SQLServerException Call: SELECT id, username, note, VERSION FROM MasatosanTest2

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  • Robust unit-testing of HTML in PHP

    - by asbja
    I'm adding unit-tests to an older PHP codebase at work. I will be testing and then rewriting a lot of HTML generation code and currently I'm just testing if the generated strings are identical to the expected string, like so: (using PHPUnit) public function testConntype_select() { $this->assertEquals( '<select><option value="blabla">Some text</option></select>', conntype_select(1); // A value from the test dataset. ); } This way has the downside that attribute ordering, whitespace and a lot of other irrelevant details are tested as well. I'm wondering if there are any better ways to do this. For example if there are any good and easy ways to compare the generated DOM trees. I found very similar questions for ruby, but couldn't find anything for PHP.

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  • Precompile Lambda Expression Tree conversions as constants?

    - by Nathan
    It is fairly common to take an Expression tree, and convert it to some other form, such as a string representation (for example this question and this question, and I suspect Linq2Sql does something similar). In many cases, perhaps even most cases, the Expression tree conversion will always be the same, i.e. if I have a function public string GenerateSomeSql(Expression<Func<TResult, TProperty>> expression) then any call with the same argument will always return the same result for example: GenerateSomeSql(x => x.Age) //suppose this will always return "select Age from Person" GenerateSomeSql(x => x.Ssn) //suppose this will always return "select Ssn from Person" So, in essence, the function call with a particular argument is really just a constant, except time is wasted at runtime re-computing it continuously. Assuming, for the sake of argument, that the conversion was sufficiently complex to cause a noticeable performance hit, is there any way to pre-compile the function call into an actual constant?

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  • Delete section of streamreader

    - by Luke
    I am reading a file into my program using streamreader. private void loadFile() { lstDeliveryDetails.Items.Clear(); if (!File.Exists("../../MealDeliveries.txt")) { MessageBox.Show("File not found!"); return; } using (StreamReader sr = new StreamReader("../../MealDeliveries.txt")) { //first line is delivery name string strDeliveryName = sr.ReadLine(); while (strDeliveryName != null) { //other lines Delivery d = new Delivery(strDeliveryName, sr.ReadLine(), sr.ReadLine(), sr.ReadLine(), sr.ReadLine(), sr.ReadLine(), sr.ReadLine()); mainForm.myDeliveries.Add(d); //check for further values strDeliveryName = sr.ReadLine(); } } displayDeliveries(); } Eventually I end up with all the deliveries in the following array public static ArrayList myDeliveries = new ArrayList(); It is loaded into the listview. I select an item as follows: iDeliverySelected = lstDeliveryDetails.SelectedItems[0].Index; I am struggling to understand how I can select an item and use a delete button to remove it from the text file?

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  • How to escape simple SQL queries in C# for SqlServer

    - by sri
    I use an API that expects a SQL string. I take a user input, escape it and pass it along to the API. The user input is quiet simple. It asks for column values. Like so: string name = userInput.Value; Then I construct a SQL query: string sql = string.Format("SELECT * FROM SOME_TABLE WHERE Name = '{0}'", name.replace("'", "''")); Is this safe enough? If it isn't, is there a simple library function that make column values safe: string sql = string.Format("SELECT * FROM SOME_TABLE WHERE Name = '{0}'", SqlSafeColumnValue(name)); The API uses SQLServer as the database. Thanks.

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  • SQL finding members who are not friends of another member

    - by thedirktastik
    I'm struggling to find a query which will return members who aren't friends of a certain member. Here is the layout of my tables: member_login: MemberID, email, password member_info: memberID, first_name, last_name member_friends: friendID, req_member, req_date, app_member, app_date, date_deactivated I tried to use NOT IN to run a query that would return the opposite of friends but nothing I try seems to be working. Here's what I thought would work: SELECT Mi.First_Name, Mi.Last_Name FROM Member_Info Mi WHERE Mi.Memberid NOT IN( SELECT Mi.Memberid, Mi.First_Name, Mi.Last_Name FROM Member_Info Mi, Member_Login Ml, Member_Friends Mf WHERE Mi.Memberid = Ml.Memberid AND (Mi.Memberid = Mf.Req_Member AND Mf.App_Member = 1 OR Mi.Memberid = Mf.App_Member AND Mf.Req_Member =1) AND Ml.Date_Deactivated <= 0 AND Mf.App_Date > 0 ); Any ideas?

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  • Mapping Repeating Sequence Groups in BizTalk

    - by Paul Petrov
    Repeating sequence groups can often be seen in real life XML documents. It happens when certain sequence of elements repeats in the instance document. Here’s fairly abstract example of schema definition that contains sequence group: <xs:schemaxmlns:b="http://schemas.microsoft.com/BizTalk/2003"            xmlns:xs="http://www.w3.org/2001/XMLSchema"            xmlns="NS-Schema1"            targetNamespace="NS-Schema1" >  <xs:elementname="RepeatingSequenceGroups">     <xs:complexType>       <xs:sequencemaxOccurs="1"minOccurs="0">         <xs:sequencemaxOccurs="unbounded">           <xs:elementname="A"type="xs:string" />           <xs:elementname="B"type="xs:string" />           <xs:elementname="C"type="xs:string"minOccurs="0" />         </xs:sequence>       </xs:sequence>     </xs:complexType>  </xs:element> </xs:schema> And here’s corresponding XML instance document: <ns0:RepeatingSequenceGroupsxmlns:ns0="NS-Schema1">  <A>A1</A>  <B>B1</B>  <C>C1</C>  <A>A2</A>  <B>B2</B>  <A>A3</A>  <B>B3</B>  <C>C3</C> </ns0:RepeatingSequenceGroups> As you can see elements A, B, and C are children of anonymous xs:sequence element which in turn can be repeated N times. Let’s say we need do simple mapping to the schema with similar structure but with different element names: <ns0:Destinationxmlns:ns0="NS-Schema2">  <Alpha>A1</Alpha>  <Beta>B1</Beta>  <Gamma>C1</Gamma>  <Alpha>A2</Alpha>  <Beta>B2</Beta>  <Gamma>C2</Gamma> </ns0:Destination> The basic map for such typical task would look pretty straightforward: If we test this map without any modification it will produce following result: <ns0:Destinationxmlns:ns0="NS-Schema2">  <Alpha>A1</Alpha>  <Alpha>A2</Alpha>  <Alpha>A3</Alpha>  <Beta>B1</Beta>  <Beta>B2</Beta>  <Beta>B3</Beta>  <Gamma>C1</Gamma>  <Gamma>C3</Gamma> </ns0:Destination> The original order of the elements inside sequence is lost and that’s not what we want. Default behavior of the BizTalk 2009 and 2010 Map Editor is to generate compatible map with older versions that did not have ability to preserve sequence order. To enable this feature simply open map file (*.btm) in text/xml editor and find attribute PreserveSequenceOrder of the root <mapsource> element. Set its value to Yes and re-test the map: <ns0:Destinationxmlns:ns0="NS-Schema2">  <Alpha>A1</Alpha>  <Beta>B1</Beta>  <Gamma>C1</Gamma>  <Alpha>A2</Alpha>  <Beta>B2</Beta>  <Alpha>A3</Alpha>  <Beta>B3</Beta>  <Gamma>C3</Gamma> </ns0:Destination> The result is as expected – all corresponding elements are in the same order as in the source document. Under the hood it is achieved by using one common xsl:for-each statement that pulls all elements in original order (rather than using individual for-each statement per element name in default mode) and xsl:if statements to test current element in the loop:  <xsl:templatematch="/s0:RepeatingSequenceGroups">     <ns0:Destination>       <xsl:for-eachselect="A|B|C">         <xsl:iftest="local-name()='A'">           <Alpha>             <xsl:value-ofselect="./text()" />           </Alpha>         </xsl:if>         <xsl:iftest="local-name()='B'">           <Beta>             <xsl:value-ofselect="./text()" />           </Beta>         </xsl:if>         <xsl:iftest="local-name()='C'">           <Gamma>             <xsl:value-ofselect="./text()" />           </Gamma>         </xsl:if>       </xsl:for-each>     </ns0:Destination>  </xsl:template> BizTalk Map editor became smarter so learn and use this lesser known feature of XSLT 2.0 in your maps and XSL stylesheets.

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  • Help with SQL query (list strings and count in same query)

    - by Mestika
    Hi everybody, I’m working on a small kind of log system to a webpage, and I’m having some difficulties with a query I want to do multiple things. I have tried to do some nested / subqueries but can’t seem to get it right. I’ve two tables: User = {userid: int, username} Registered = {userid: int, favoriteid: int} What I need is a query to list all the userid’s and the usernames of each user. In addition, I also need to count the total number of favoriteid’s the user is registered with. A user who is not registered for any favorite must also be listed, but with the favorite count shown as zero. I hope that I have explained my request probably but otherwise please write back so I can elaborate. By the way, the query I’ve tried with look like this: SELECT user.userid, user.username FROM user,registered WHERE user.userid = registered.userid(SELECT COUNT(favoriteid) FROM registered) However, it doesn’t do the trick, unfortunately Kind regards Mestika

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  • How do I get the child of a unique parent in ActionScript?

    - by Koen
    My question is about targeting a child with a unique parent. For example. Let's say I have a box people can move called box_mc and 3 platforms it can jump on called: Platform_1 Platform_2 Platform_3 All of these platforms have a child element called hit. Platform_1 Hit Platform_2 Hit Platform_3 Hit I use an array and a for each statement to detect if box_mc hits one of the platforms childs. var obj_arr:Array = [Platform_1, Platform_2, Platform_3]; for each(obj in obj_arr){ if(box_mc.hitTestObject(obj.hit)){ trace(obj + " " + obj.hit); box_mc.y = obj.hit.y - box_mc.height; } } obj seems to output the unique parent it is hitting but obj.hit ouputs hit, so my theory is that it is applying the change of y to all the childs called hit in the stage. Would it be possible to only detect the child of that specific parent?

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  • How to calculate real-time stats?

    - by Diego Jancic
    I have a site with millions of users (well, actually it doesn't have any yet, but let's imagine), and I want to calculate some stats like "log-ins in the past hour". The problem is similar to the one described here: http://highscalability.com/blog/2008/4/19/how-to-build-a-real-time-analytics-system.html The simplest approach would be to do a select like this: select count(distinct user_id) from logs where date>='20120601 1200' and date <='20120601 1300' (of course other conditions could apply for the stats, like log-ins per country) Of course this would be really slow, mainly if it has millions (or even thousands) of rows, and I want to query this every time a page is displayed. How would you summarize the data? What should go to the (mem)cache? EDIT: I'm looking for a way to de-normalize the data, or to keep the cache up-to-date. For example I could increment an in-memory variable every time someone logs in, but that would help to know the total amount of logins, not the "logins in the last hour". Hope it's more clear now.

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  • Simple database design and LINQ

    - by Anders Svensson
    I have very little experience designing databases, and now I want to create a very simple database that does the same thing I have previously had in xml. Here's the xml: <services> <service type="writing"> <small>125</small> <medium>100</medium> <large>60</large> <xlarge>30</xlarge> </service> <service type="analysis"> <small>56</small> <medium>104</medium> <large>200</large> <xlarge>250</xlarge> </service> </services> Now, I wanted to create the same thing in a SQL database, and started doing this ( hope this formats ok, but you'll get the gist, four columns and two rows): > ServiceType Small Medium Large > > Writing 125 100 60 > > Analysis 56 104 200 This didn't work too well, since I then wanted to use LINQ to select, say, the Large value for Writing (60). But I couldn't use LINQ for this (as far as I know) and use a variable for the size (see parameters in the method below). I could only do that if I had a column like "Size" where Small, Medium, and Large would be the values. But that doesn't feel right either, because then I would get several rows with ServiceType = Writing (3 in this case, one for each size), and the same for Analysis. And if I were to add more servicetypes I would have to do the same. Simply repetitive... Is there any smart way to do this using relationships or something? Using the second design above (although not good), I could use the following LINQ to select a value with parameters sent to the method: protected int GetHourRateDB(string serviceType, Size size) { CalculatorLinqDataContext context = new CalculatorLinqDataContext(); var data = (from calculatorData in context.CalculatorDatas where calculatorData.Service == serviceType && calculatorData.Size == size.ToString() select calculatorData).Single(); return data.Hours; } But if there is another better design, could you please also describe how to do the same selection using LINQ with that design? Please keep in mind that I am a rookie at database design, so please be as explicit and pedagogical as possible :-) Thanks! Anders

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  • Linq and Lamba Expressions - while walking a selected list perform an action

    - by Prescott
    Hey, I'm very new to linq and lamba expressions. I'm trying to walk a collection, and when I find an item that meets some criteria I'd like to add that to another separate collection. My linq to walk the collection looks like this (this works fine): From i as MyCustomItem In MyCustomItemCollection Where i.Type = "SomeType" Select i I need each of the select items to then be added to a ListItemCollection, I know I can assign that linq query to a variable, and then do a for each loop adding a new ListItem to the collection, but I'm trying o find a way to add each item to the new ListItemcollection while walking, not a second loop. Thanks ~P

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