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Caveats of select/poll vs. epoll reactors in Twisted

...o based apps ) leads me to believe that ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price. ...
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Optimal way to concatenate/aggregate strings

...Transact SQL, which should work fine in Azure. ;WITH Partitioned AS ( SELECT ID, Name, ROW_NUMBER() OVER (PARTITION BY ID ORDER BY Name) AS NameNumber, COUNT(*) OVER (PARTITION BY ID) AS NameCount FROM dbo.SourceTable ), Concatenated AS ( SELECT ...
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How do I execute a stored procedure once for each row returned by query?

... declare @field1 int declare @field2 int declare cur CURSOR LOCAL for select field1, field2 from sometable where someotherfield is null open cur fetch next from cur into @field1, @field2 while @@FETCH_STATUS = 0 BEGIN --execute your sproc on each row exec uspYourSproc @field1, @fiel...
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MySQL Error 1093 - Can't specify target table for update in FROM clause

...s question In MySQL, you can't modify the same table which you use in the SELECT part. This behaviour is documented at: http://dev.mysql.com/doc/refman/5.6/en/update.html Maybe you can just join the table to itself If the logic is simple enough to re-shape the query, lose the subquery and join th...
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Html.DropdownListFor selected value not being set

How can I set the selected value of a Html.DropDownListFor? I've been having a look online and have seen that it can be achieved by using the fourth parameter so like the below: ...
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INSERT INTO…SELECT for all MySQL columns

... manual. Try this: INSERT INTO this_table_archive (col1, col2, ..., coln) SELECT col1, col2, ..., coln FROM this_table WHERE entry_date < '2011-01-01 00:00:00'; If the id columns is an auto-increment column and you already have some data in both tables then in some cases you may want to omit t...
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how to emulate “insert ignore” and “on duplicate key update” (sql merge) with postgresql?

... two queries, one for INSERT and one for UPDATE (as an appropriate join/subselect of course - no need to write your main filter twice) share | improve this answer | follow ...
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Get index of selected option with jQuery

I'm a little bit confused about how to get an index of a selected option from a HTML <select> item. 7 Answers ...
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Find a value anywhere in a database

...OT NULL BEGIN SET @ColumnName = '' SET @TableName = ( SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME)) FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE = 'BASE TABLE' AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) &...
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How do you check what version of SQL Server for a database using TSQL?

... Try SELECT @@VERSION or for SQL Server 2000 and above the following is easier to parse :) SELECT SERVERPROPERTY('productversion') , SERVERPROPERTY('productlevel') , SERVERPROPERTY('edition') From: http://support....