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  • NHibernate not dropping foreign key constraints.

    - by Kendrick
    I'm new to NHibernate, so this is probably my mistake, but when I use: schema.Create(true, true); I get: SchemaExport [(null)]- There is already an object named 'XXX' in the database. System.Data.SqlClient.SqlException: There is already an object named 'XXX' in the database. I grabbed the SQL code nHibernate was using, ran it directly from MSSMS, and recieved similar errors. Looking into it, the generated code is not properly dropping the foreign key constraints. The drop looks like this: if exists (select 1 from sysobjects where id = OBJECT_ID(N'dbo[FK22212EAFBFE4C58]') AND parent_obj = OBJECT_ID('YYY')) alter table dbo.YYY drop constraint FK22212EAFBFE4C58 Doing a "select OBJECT_ID(N'dbo[FK22212EAFBFE4C58]')" I get null. If I take out the "dbo" (i.e. "select OBJECT_ID(N'[FK22212EAFBFE4C58]')") then the ID is returned. So, my question is, why is nHibernate adding the dbo, and why does that prevent the object from being returned (since the table owning the constraint is dbo.XXX) One of my mapping files: <?xml version="1.0" encoding="utf-8"?> <hibernate-mapping namespace="CanineApp.Model" assembly="CanineApp.Model" xmlns="urn:nhibernate-mapping-2.2"> <class name="MedicalLog" table="MedicalLog" schema="dbo"> <id name="MedicalLogID" type="Int64"> <generator class="identity" /> </id> <property name="InvoiceAmount" type="Decimal" not-null="true" /> ... <many-to-one name="Canine" class="Canine" column="CanineID" not-null="true" fetch="join" /> <many-to-one name="TreatmentCategory" class="TreatmentCategory" column="TreatmentCategoryID" not-null="true" access="field.camelcase-underscore" /> </class> </hibernate-mapping>

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  • Grouping by date, with 0 when count() yields no lines

    - by SCO
    I'm using Postgresql 9 and I'm fighting with counting and grouping when no lines are counted. Let's assume the following schema : create table views { date_event timestamp with time zone ; event_id integer; } Let's imagine the following content : 2012-01-01 00:00:05 2 2012-01-01 01:00:05 5 2012-01-01 03:00:05 8 2012-01-01 03:00:15 20 I want to group by hour, and count the number of lines. I wish I could retrieve the following : 2012-01-01 00:00:00 1 2012-01-01 01:00:00 1 2012-01-01 02:00:00 0 2012-01-01 03:00:00 2 2012-01-01 04:00:00 0 2012-01-01 05:00:00 0 . . 2012-01-07 23:00:00 0 I mean that for each time range slot, I count the number of lines in my table whose date correspond, otherwise, I return a line with a count at zero. The following will definitely not work (will yeld only lines with counted lines 0). SELECT extract ( hour from date_event ),count(*) FROM views where date_event > '2012-01-01' and date_event <'2012-01-07' GROUP BY extract ( hour from date_event ); Please note I might also need to group by minute, or by hour, or by day, or by month, or by year (multiple queries is possible of course). I can only use plain old sql, and since my views table can be very big (100M records), I try to keep performance in mind. How can this be achieved ? Thank you !

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  • LINQ - 'Could not translate expression' with previously used and proven query condition

    - by tomfumb
    I am fairly new to LINQ and can't get my head around some inconsistency in behaviour. Any knowledgeable input would be much appreciated. I see similar issues on SO and elsewhere but they don't seem to help. I have a very simple setup - a company table and an addresses table. Each company can have 0 or more addresses, and if 0 one must be specified as the main address. I'm trying to handle the cases where there are 0 addresses, using an outer join and altering the select statement accordingly. Please note I'm currently binding the output straight to a GridView so I would like to keep all processing within the query. The following DOES work IQueryable query = from comp in context.Companies join addr in context.Addresses on comp.CompanyID equals addr.CompanyID into outer // outer join companies to addresses table to include companies with no address from addr in outer.DefaultIfEmpty() where (addr.IsMain == null ? true : addr.IsMain) == true // if a company has no address ensure it is not ruled out by the IsMain condition - default to true if null select new { comp.CompanyID, comp.Name, AddressID = (addr.AddressID == null ? -1 : addr.AddressID), // use -1 to represent a company that has no addresses MainAddress = String.Format("{0}, {1}, {2} {3} ({4})", addr.Address1, addr.City, addr.Region, addr.PostalCode, addr.Country) }; but this displays an empty address in the GridView as ", , ()" So I updated the MainAddress field to be MainAddress = (addr.AddressID == null ? "" : String.Format("{0}, {1}, {2} {3} ({4})", addr.Address1, addr.City, addr.Region, addr.PostalCode, addr.Country)) and now I'm getting the Could not translate expression error and a bunch of spewey auto-generated code in the error which means very little to me. The condition I added to MainAddress is no different to the working condition on AddressID, so can anybody tell me what's going on here? Any help greatly appreciated.

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  • Union and order by

    - by David Lively
    Consider a table like tbl_ranks -------------------------------- family_id | item_id | view_count -------------------------------- 1 10 101 1 11 112 1 13 109 2 21 101 2 22 112 2 23 109 3 30 101 3 31 112 3 33 109 4 40 101 4 51 112 4 63 109 5 80 101 5 81 112 5 88 109 I need to generate a result set with the top two(2) rows for a subset of family ids (say, 1,2,3 and 4) ordered by view count. I'd like to do something like select top 2 * from tbl_ranks where family_id = 1 order by view_count union all select top 2 * from tbl_ranks where family_id = 2 order by view_count union all select top 2 * from tbl_ranks where family_id = 3 order by view_count union all select top 2 * from tbl_ranks where family_id = 4 order by view_count but, of course, order by isn't valid in a union all context in this manner. Any suggestions? I know I could run a set of 4 queries, store the results into a temp table and select the contents of that temp as the final result, but I'd rather avoid using a temp table if possible. Note: in the real app, the number of records per family id is indeterminate, and the view_counts are also not fixed as they appear in the above example.

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  • Dynamic SQL and Funtions

    - by Unlimited071
    Hi all, is there any way of accomplishing something like the following: CREATE FUNCTION GetQtyFromID ( @oricod varchar(15), @ccocod varchar(15), @ocmnum int, @oinnum int, @acmnum int, @acttip char(2), @unisim varchar(15) ) AS BEGIN DECLARE @Result decimal(18,8) DECLARE @SQLString nvarchar(max); DECLARE @ParmDefinition nvarchar(max); --I need to execute a query stored in a cell which returns the calculated qty. --i.e of AcuQry: select @cant = sum(smt) from table where oricod = @oricod and ... SELECT @SQLString = AcuQry FROM OinActUni WHERE (OriCod = @oricod) AND (ActTipCod = @acttip) AND (UniSim = @unisim) AND (AcuEst > 0) SET @ParmDefinition = N' @oricod varchar(15), @ccocod varchar(15), @ocmnum int, @oinnum int, @acmnum int, @cant decimal(18,8) output'; EXECUTE sp_executesql @SQLString, @ParmDefinition, @oricod = @oricod, @ccocod = @ccocod, @ocmnum = @ocmnum, @oinnum = @oinnum, @acmnum = @acmnum, @cant = @result OUTPUT; RETURN @Result END The problem with this approach is that it is prohibited to execute sp_excutesql in a function... What I need is to do something like: select id, getQtyFromID(id) as qty from table The main idea is to execute a query stored in a table cell, this is because the qty of something depends on it's unit. the unit can be days or it can be metric tons, so there is no relation between the units, therefore the need of a specific query for each unit.

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  • SQL -- How is DISTINCT so fast without an index?

    - by Jonathan
    Hi, I have a database with a table called 'links' with 600 million rows in it in SQLite. There are 2 columns in the database - a "src" column and a "dest" column. At present there are no indices. There are a fair number of common values between src and dest, but also a fair number of duplicated rows. The first thing I'm trying to do is remove all the duplicate rows, and then perform some additional processing on the results, however I've been encountering some weird issues. Firstly, SELECT * FROM links WHERE src=434923 AND dest=5010182. Now this returns one result fairly quickly and then takes quite a long time to run as I assume it's performing a tablescan on the rest of the 600m rows. However, if I do SELECT DISTINCT * FROM links, then it immediately starts returning rows really quickly. The question is: how is this possible?? Surely for each row, the row must be compared against all of the other rows in the table, but this would require a tablescan of the remaining rows in the table which SHOULD takes ages! Any ideas why SELECT DISTINCT is so much quicker than a standard SELECT?

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  • find a duplicate series in SQL

    - by SomeMiscGuy
    I have a table with 3 columns containing a variable number of records based off of the first column which is a foreign key. I am trying to determine if I can detect when there is a duplicate across multiple rows for an entire series declare @finddupseries table ( portid int, asset_id int, allocation float ) ; INSERT INTO @finddupseries SELECT 250, 6, 0.05 UNION ALL SELECT 250, 66, 0.8 UNION ALL SELECT 250, 2, 0.105 UNION ALL SELECT 250, 4, 0.0225 UNION ALL SELECT 250, 5, 0.0225 UNION ALL SELECT 251, 13, 0.6 UNION ALL SELECT 251, 2, 0.3 UNION ALL SELECT 251, 5, 0.1 UNION ALL SELECT 252, 13, 0.8 UNION ALL SELECT 252, 2, 0.15 UNION ALL SELECT 252, 5, 0.05 UNION ALL SELECT 253, 13, 0.4 UNION ALL SELECT 253, 2, 0.45 UNION ALL SELECT 253, 5, 0.15 UNION ALL SELECT 254, 6, 0.05 UNION ALL SELECT 254, 66, 0.8 UNION ALL SELECT 254, 2, 0.105 UNION ALL SELECT 254, 4, 0.0225 UNION ALL SELECT 254, 5, 0.0225 select * from @finddupseries The records for portid 250 and 254 match. Is there any way I can write a query to detect this? edit: yes, the entire series must match. Also, if there was a way to determine which one it DID match would be helpful as the actual table has around 10k records. thanks!

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  • Creating a Variable From Two Others

    - by John
    Hello, In the HTML table below, I would like to add a third column that equals $row["countSubmissions"] times 10 plus $row["countComments"]. How could I do this? Thanks in advance, John $sqlStr = "SELECT l.loginid, l.username, COALESCE(s.total, 0) AS countSubmissions, COALESCE(c.total, 0) AS countComments FROM login l LEFT JOIN ( SELECT loginid, COUNT(1) AS total FROM submission GROUP BY loginid ) s ON l.loginid = s.loginid LEFT JOIN ( SELECT loginid, COUNT(1) AS total FROM comment GROUP BY loginid ) c ON l.loginid = c.loginid GROUP BY l.loginid ORDER BY countSubmissions DESC LIMIT 10"; $result = mysql_query($sqlStr); $arr = array(); echo "<table class=\"samplesrec1edit\">"; while ($row = mysql_fetch_array($result)) { echo '<tr>'; echo '<td class="sitename1edit1"><a href="http://www...com/.../members/index.php?profile='.$row["username"].'">'.stripslashes($row["username"]).'</a></td>'; echo '<td class="sitename1edit2">'.stripslashes($row["countSubmissions"]).'</td>'; echo '<td class="sitename1edit2">'.stripslashes($row["countComments"]).'</td>'; echo '</tr>'; } echo "</table>";

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  • Mysql query, need suggestion or solution

    - by Xi Kam
    Can anyone help me, i have two tables and i need records from both the table //////////////////////////////++ Query 1 ++//////////////////////////////////// SELECT SUM(rec_issued) AS issed, regen_id, YEAR(issue_date) AS iYear, MONTH(issue_date) AS iMonth FROM `view_rec_issued` WHERE `regen_id` = 2 GROUP BY YEAR(issue_date) DESC, MONTH(issue_date) DESC ORDER BY issue_date ASC issed regen_id iYear iMonth 424 2 2011 3 4340 2 2011 4 4235 2 2011 5 10570 2 2012 2 4761 2 2012 3 5000 2 2012 4 3700 2 2012 5 3414 2 2012 6 3700 2 2012 7 2992 2 2012 8 995 2 2012 10 ![Result from Query 1][1] //////////////////////////////++ Query 2 ++//////////////////////////////////// SELECT SUM(total_redem) AS redemed, regen_id, YEAR(redemption_date) AS rYear, MONTH(redemption_date) AS rMonth FROM `recredem_month_wise` WHERE `regen_id` = 2 GROUP BY YEAR(redemption_date) DESC, MONTH(redemption_date) DESC order by redemption_date ASC redemed regen_id rYear rMonth 424 2 2011 3 260 2 2011 4 6523 2 2011 5 1070 2 2011 6 200 2 2011 10 500 2 2011 11 9750 2 2012 2 5000 2 2012 3 5500 2 2012 4 3803 2 2012 5 3700 2 2012 7 3000 2 2012 8 ![Result from Query 2][2] But i want it as - issed regen_id iYear iMonth redemed regen_id rYear rMonth 424 2 2011 3 424 2 2011 3 4340 2 2011 4 260 2 2011 4 4235 2 2011 5 6523 2 2011 5 NULL NULL NULL NULL 1070 2 2011 6 NULL NULL NULL NULL 200 2 2011 10 NULL NULL NULL NULL 500 2 2011 11 10570 2 2012 2 9750 2 2012 2 4761 2 2012 3 5000 2 2012 3 5000 2 2012 4 5500 2 2012 4 3700 2 2012 5 3803 2 2012 5 3414 2 2012 6 NULL NULL NULL NULL 3700 2 2012 7 3700 2 2012 7 2992 2 2012 8 3000 2 2012 8 995 2 2012 10 NULL NULL NULL NULL ![I want this output][3] In these table regen_id is unique and i need data as YEAR and MONTH, if in any table not have the records in perticular month and year it should retrieve zero or null. But in every record year and month should equal like this - iYear = rYear and iMonth = rMonth So we can merge both the fields - No need to show year and month twice iYear and rYear = year iMonth and rMonth = month Thank You Please look at this problem.

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  • What is a good solution to log the deletion of a row in MySQL?

    - by hobodave
    Background I am currently logging deletion of rows from my tickets table at the application level. When a user deletes a ticket the following SQL is executed: INSERT INTO alert_log (user_id, priority, priorityName, timestamp, message) VALUES (9, 4, 'WARN', NOW(), "TICKET: David A. deleted ticket #6 from Foo"); Please do not offer schema suggestions for the alert_log table. Fields: user_id - User id of the logged in user performing the deletion priority - Always 4 priorityName - Always 'WARN' timestamp - Always NOW() message - Format: "[NAMESPACE]: [FullName] deleted ticket #[TicketId] from [CompanyName]" NAMESPACE - Always TICKET FullName - Full name of user identified by user_id above TicketId - Primary key ID of the ticket being deleted CompanyName - Ticket has a Company via tickets.company_id Situation/Questions Obviously this solution does not work if a ticket is deleted manually from the mysql command line client. However, now I need to. The issues I'm having are as follows: Should I use a PROCEDURE, FUNCTION, or TRIGGER? -- Analysis: TRIGGER - I don't think this will work because I can't pass parameters to it, and it would trigger when my application deleted the row too. PROCEDURE or FUNCTION - Not sure. Should I return the number of deleted rows? If so, that would require a FUNCTION right? How should I account for the absence of a logged in user? -- Possibilities: Using either a PROC or FUNC, require the invoker to pass in a valid user_id Require the user to pass in a string with the name Use the CURRENT_USER - meh Hard code the FullName to just be "Database Administrator" Could the name be an optional parameter? I'm rather green when it comes to sprocs. Assuming I went with the PROC/FUNC approach, is it possible to outright restrict regular DELETE calls to this table, yet still allow users to call this PROC/FUNC to do the deletion for them? Ideally the solution is usable by my application as well, so that my code is DRY.

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  • Reload a UITable on the fly when editing a UITextField inside one of the cells

    - by Saze
    I have a UITable containing some customs UITableCells. Those cells contain a few UILabels and a UITextField. The datasource of the table comes from a main controller's property. (This controller is also the delegate and the dataSource for the table). Here's a simplified screenshot of the UI: Now, I need to update "on the fly" the content of all the UILabels when the user edits one of the UITextFields. To do so, at the I am listening to the "Editing Changed" event at the UITextField level. This triggers the following action: - (IBAction) editChangeHandler: (id) sender { MyAppDelegate *delegate = [[UIApplication sharedApplication] delegate]; [[delegate.viewController.myDataSourceArray objectAtIndex:self.rowIndex] setANumber: [theTextField.text intValue]]; [delegate.viewController reloadRows]; } The reloadRows method in the viewController is as such: - (void) reloadRows { NSLog(@"called reloadRows"); //perform some calculations on the data source objects here... [theUITable reloadData]; } My problem here is that whenever the user changes the value in the field, the reloadRows method is successfully called, so is apparently the reloadData but it also causes the keyboard to be dismissed. So in the end, the user can only touch one key when editing the TextField before the keyboard is dismissed and the table reloaded. Does anybody knows a solution to this or have experienced the same issue?

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  • customized form_for tag in rails

    - by poseid
    I want to make a table within a form by making a new form_tag. The following code in ApplicationHelper fails: module ApplicationHelper class TabularFormBuilder < ActionView::Helpers::FormBuilder # ... code to insert <tr> tags </tr> end def tabular_form_for(name, object = nil, options = nil, &proc) concat("<table>", proc.binding) form_for(name, object, (options||{}).merge(:builder => TabularFormBuilder), &proc) concat("</table>", proc.binding) end end The view I use is: <h1>New project</h1> <% tabular_form_for :project, :builder => ApplicationHelper::TabularFormBuilder do |f| %> <%= f.error_messages %> <%= f.text_field :name %> <%= f.text_area :description %> <%= f.text_field :location %> <%= f.submit 'Create' %> <% end %> The error I get is: NoMethodError in Projects#new Showing app/views/projects/new.html.erb where line #5 raised: undefined method `errors' for {:builder=ApplicationHelper::TabularFormBuilder}:Hash Any ideas how to make this custom tag work?

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  • Hibernate many-to-many relationship

    - by Capitan
    I have two mapped types, related many-to-many. @Entity @Table(name = "students") public class Student{ ... @ManyToMany(fetch = FetchType.EAGER) @JoinTable( name = "students2courses", joinColumns = { @JoinColumn( name = "student_id", referencedColumnName = "_id") }, inverseJoinColumns = { @JoinColumn( name = "course_id", referencedColumnName = "_id") }) public Set<Course> getCourses() { return courses; } public void setCourses(Set<Course> courses) { this.courses = courses; } ... } __ @Entity @Table(name = "courses") public class Course{ ... @ManyToMany(fetch = FetchType.EAGER, mappedBy = "courses") public Set<Student> getStudents() { return students; } public void setStudents(Set<Student> students) { this.students = students; } ... } But if I update/delete Course entity, records are not created/deleted in table students2courses. (with Student entity updating/deleting goes as expected) I wrote abstract class HibObject public abstract class HibObject { public String getRemoveMTMQuery() { return null; } } which is inherited by Student and Course. In DAO I added this code (for delete() method): String query = obj.getRemoveMTMQuery(); if (query != null) { session.createSQLQuery(query).executeUpdate(); } and I ovrerided method getRemoveMTMQuery() for Course @Override @Transient public String getRemoveMTMQuery() { return "delete from students2courses where course_id = " + id + ";"; } Now it works but I think it's a bad code. Is there a best way to solve this problem?

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  • Bind data of interface properties only

    - by nivpenso
    I am new in all the Entity Framework models and the data bindings. I created an interface and generated a model class from my Candidate table in the db. public interface ICandidate { String ID { get; set; } string Name { get; set; } string Mail { get; set; } } i created a partial class to the generated Candidate model so i will be able to implement the ICandidate interface without changing any generated code. public partial class Candidates : ICandidate { string ICandidate.ID { get { return this.PK; } set { _PK = value; } } string ICandidate.Name { get{ return this._Name; } set { _Name = value; } } string ICandidate.Mail { get { return this._Email; } set { this._Email = value; } } } Of course, the generated class has more properties than the interface has (Like IsDeleted field that is not necessary for the interface). I want to display in a DataGridView all the candidates from the db. But I want that only the interface's properties will be shown as columns in the DataGridView. Is there a way bind only the interface's properties the the DataGridView? In my DB there is a table called Candidate_To_Company with these columns: PK, Candidate_FK, Company_FK, Insertion_Date I would like to bind this table to DataGridView. but instead of displaying Candidate_FK i would like to display the candidate name from ICandidate. Is this possible?

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  • SQL queries to determine all values that would satisfy an arbitrary query

    - by jasterm007
    I'm trying to figure out how to efficiently run a set of queries that will provide a new table of all values that would return results for an arbitrary query. Say my table has a schema like: id name age city What is an efficient way to list all values that would return results for an arbitrary query, say "NOT city=X AND age BETWEEN Y and Z"? My naive approach for this would be to use a script and recurse through all possible combinations of {city, age, age} and see which SELECTs return more than 0 results, but that seems incredibly inefficient. I've also tried building large joins on {city, age, age} as well and basically using that table as an argument list to the query, but that quickly becomes an impossibility for queries on many columns. For simple conjunctive equality queries, i.e. "name=X and age=Y", this is much simpler, as I can do something like SELECT name, age, count(*) AS count FROM main GROUP BY name, age HAVING count > 0 But I'm having difficulty coming up with a general approach for anything more complicated than that. Any pointers in the right direction would be most helpful, thanks.

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  • Automatically Persisting a Complex Java Object

    - by VeeArr
    For a project I am working on, I need to persist a number of POJOs to a database. The POJOs class definitions are sometimes highly nested, but they should flatten okay, as the nesting is tree-like and contains no cycles (and the base elements are eventually primitives/Strings). It is preferred that the solution used create one table per data type and that the tables will have one field per primitive member in the POJO. Subclassing and similar problems are not issues for this particular project. Does anybody know of any existing solutions that can: Automatically generate a CREATE TABLE definition from the class definition Automatically generate a query to persist an object to the database, given an instance of the object Automatically generate a query to retrieve an object from the database and return it as a POJO, given a key. Solutions that can do this with minimum modifications/annotions to the class files and minimum external configuration are preferred. Example: Java classes //Class to be persisted class TypeA { String guid; long timestamp; TypeB data1; TypeC data2; } class TypeB { int id; int someData; } class TypeC { int id; int otherData; } Could map to CREATE TABLE TypeA ( guid CHAR(255), timestamp BIGINT, data1_id INT, data1_someData INT, data2_id INt, data2_otherData INT ); Or something similar.

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  • Intelligently removing excess indention from a string

    - by TravisO
    I'm trying to remove some excessive indention from a string, in this case it's SQL, so it can be put into a log file. So I need the find the smallest amount of indention (aka tabs) and remove it from the front of each line, but the following code ends up printing out exactly the same, any ideas? In other words, I want to take the following SELECT blah FROM table WHERE id=1 and convert it to SELECT blah FROM table WHERE id=1 here's the code I tried and fails $sql = ' SELECT blah FROM table WHERE id=1 '; // it's most likely idented SQL, remove any idention $lines = explode("\n", $sql); $space_count = array(); foreach ( $lines as $line ) { preg_match('/^(\t+)/', $line, $matches); $space_count[] = strlen($matches[0]); } $min_tab_count = min($space_count); $place = 0; foreach ( $lines as $line ) { $lines[$place] = preg_replace('/^\t{'. $min_tab_count .'}/', '', $line); $place++; } $sql = implode("\n", $lines); print '<pre>'. $sql .'</pre>';

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  • HTML5 card game [closed]

    - by ChrisCa
    I created a card game in silverlight a year or so ago in order to learn a bit about Silverlight. I am now wanting to make a HTML5 version of the game in an effort to learn a little bit more about that. I am thinking I'd like to take advantage of stuff like Knockout.js and WebSockets and the canvas element. Now what I'm confused about is how to lay out the cards on the screen. With Silverlight I was able to make a "Hand" control, which was made up of two sub controls - the cards the player has in their hand and the ones they have on the table. And they in turn were made up of Card controls. Now I don't believe there is the concept on a User Control in javascript. So I am possibly thinking about this in entirely the wrong way. So my question is - how could I lay out some cards on the table and perhaps make reuse of something for each player? I have a client side JSON object called game, which contains an array of players. Each player has a hand which is made up of an array of in-hand cards and on-table cards. Ideally I would like to bind these to something using Knockout.js - but I don't know what I could bind to. Would I simply position images (of cards) on a canvas? Is there a way to make some kind of Hand object that each player could have and that I could bind to? Any advice? Or sample code you've seen elsewhere?

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  • find the difference between two very large list

    - by user157195
    I have two large list(could be a hundred million items), the source of each list can be either from a database table or a flat file. both lists are of comparable sizes, both unsorted. I need to find the difference between them. so I have 3 scenarios: 1. List1 is a database table(assume each row simply have one item(key) that is a string), List2 is a large file. 2. Both lists are from 2 db tables. 3. both lists are from two files. in case 2, I plan to use: select a.item from MyTable a where a.item not in (select b.item form MyTable b) this clearly is inefficient, is there a better way? Another approach is: I plan to sort each list, and then walk down both of them to find the diff. If the list is from a file, I have to read it into a db table first, then use db sorting to output the list. Is the run time complexity still O(nlogn) in db sorting? either approach is a pain and seems would be very slow when the list involved has hundreds of millions of items. any suggestions?

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  • Displaying Query Results Horizontally

    - by AndyD273
    I am wondering if it is possible to take the results of a query and return them as a CSV string instead of as a column of cells. Basically, we have a table called Customers, and we have a table called CustomerTypeLines, and each Customer can have multiple CustomerTypeLines. When I run a query against it, I run into problems when I want to check multiple types, for instance: Select * from Customers a Inner Join CustomerTypeLines b on a.CustomerID = b.CustomerID where b.CustomerTypeID = 14 and b.CustomerTypeID = 66 ...returns nothing because a customer can't have both on the same line, obviously. In order to make it work, I had to add a field to Customers called CustomerTypes that looks like ,14,66,67, so I can do a Where a.CustomerTypes like '%,14,%' and a.CustomerTypes like '%,66,%' which returns 85 rows. Of course this is a pain because I have to make my program rebuild this field for that Customer each time the CustomerTypeLines table is changed. It would be nice if I could do a sub query in my where that would do the work for me, so instead of returning the results like: 14 66 67 it would return them like ,14,66,67, Is this possible?

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  • '<=' operator is not working in sql server 2000

    - by Lalit
    Hello, Scenario is, database is in the maintenance phase. this database is not developed by ours developer. it is an existing database developed by the 'xyz' company in sql server 2000. This is real time database, where i am working now. I wanted to write the stored procedure which will retrieve me the records From date1 to date 2.so query is : Select * from MyTableName Where colDate>= '3-May-2010' and colDate<= '5-Oct-2010' and colName='xyzName' whereas my understanding I must get data including upper bound date as well as lower bound date. but somehow I am getting records from '3-May-2010' (which is fine but) to '10-Oct-2010' As i observe in table design , for ColDate, developer had used 'varchar' to store the date. i know this is wrong remedy by them. so in my stored procedure I have also used varchar parameters as @FromDate1 and @ToDate to get inputs for SP. this is giving me result which i have explained. i tried to take the parameter type as 'Datetime' but it is showing error while saving/altering the stored procedure that "@FromDate1 has invalid datatype", same for "@ToDate". situation is that, I can not change the table design at all. what i have to do here ? i know we can use user defined table in sql server 2008 , but there is version sql server 2000. which does not support the same. Please guide me for this scenario. **Edited** I am trying to write like this SP: CREATE PROCEDURE USP_Data (@Location varchar(100), @FromDate DATETIME, @ToDate DATETIME) AS SELECT * FROM dbo.TableName Where CAST(Dt AS DATETIME) >=@fromDate and CAST(Dt AS DATETIME)<=@ToDate and Location=@Location GO but getting Error: Arithmetic overflow error converting expression to data type datetime. in sql server 2000 What should be that ? is i am wrong some where ? also (202 row(s) affected) is changes every time in circular manner means first time sayin (122 row(s) affected) run again saying (80 row(s) affected) if again (202 row(s) affected) if again (122 row(s) affected) I can not understand what is going on ?

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  • Need help making a div appear on the bottom of the screen while the rest of the divs scroll

    - by user1896600
    It's hard to describe my specific problem without just showing you the HTML code. The HTML source can be seen easily from clicking "View Source" while seeing the page http://techdot.us/projects/jeopardy/view.php. The CSS is located here: http://techdot.us/projects/jeopardy/style/gameStyle.css. My main goal is to have the main content table rows/columns appear on the majority of the screen (everything except 69px, to be exact). So, the bottom 69px contains an informational panel that is supposed to stay on the bottom of the screen, even when the user scrolls down the page. Scrolling is supposed to, in theory, trigger the majority of the content to go down the page normally, except the bottom bar which stays static. I have achieved this effect on the website. However, there is a big problem. On smaller screens (as you can simulate by resizing the window), some of the main table gets cut off. It seems that my CSS solution is a botch, and, in effect, does not accomplish my main goal. The bottom bar should not cut off part of the table from the main content div (gameTable), but the main content div should display all of its content in a scrollable fashion. My CSS at the moment works as long as the viewer's screen is a certain pixel height. This is definitely not permanent. Thank you SO much for the help. I really appreciate it and totally understand that I'm being a total pain by just throwing down tons of CSS and HTML code to edit.

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  • Adding up row number and displaying total using COUNT (PHP MySQL)

    - by Yvonne
    I'm attempting to run a query that adds up the total number of subjects in a class. A class has many subjects. There is a 'teachersclasses' table between teachers (the user table) and classes. The principles sounds pretty simple but I'm having some trouble in getting my page to display the number of subjects for each class (directly associated with the teacher) This is what I have so far, trying to make use of the COUNT with a nested SELECT: SELECT (SELECT count(*) FROM subjects WHERE subjects.classid = class.classid) AS total_subjects, class.classname, class.classid FROM class Then I am calling up 'num_subjects' to present the total within a while loop: <?php echo $row['total_subjects']?> From the above, I am receiving the total subjects for a class, but within the same table row (for one class) and my other while loop doesnt run anymore, which returns all of the classes associated with a teacher :( ... Bit of a mess now! I know to return the classes for a particular teacher, I can do an additional WHERE clause on the session of 'teacherid' but I think my query is getting too complicated for me that errors are popping up everywhere. Anyone have a quick fix for this! Thanks very much

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  • Thread-safe get (accessor method)

    - by sonofdelphi
    I'm currently using the following code for thread-safe access of a variable. int gnVariable; void getVariableValue(int *pnValue) { acquireLock(); //Acquires the protection mechanism *pnValue = gnVariable; releaseLock(); //Releasing the protection mechanism } I would like to change my API signature to a more user-friendly int getVariableValue(void); How should I rewrite the function - such that the users of the API don't have to bother about the locking/unlocking details?

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  • Please suggest good book/website to for Threads and Concurrency?

    - by learner
    I have gone through Head First Java and some other sites but I couldn't find complete stuff related to Threads and additional concurrency packages at one place. Please suggest a book/website which covers complete Threads with more details like Synchronize and locking of objects More detailed about volatile Visibility issues in Threads java.util.concurrent package java.util.concurrent.atomic package

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