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MySQL indexes - what are the best practices?
...t them. Generally I put an index on any fields that I will be searching or selecting using a WHERE clause but sometimes it doesn't seem so black and white.
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How to check if a column exists in a SQL Server table?
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SQL Server 2005 onwards:
IF EXISTS(SELECT 1 FROM sys.columns
WHERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tabl...
How do I generate a constructor from class fields using Visual Studio (and/or ReSharper)?
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ReSharper offers a Generate Constructor tool where you can select any field/properties that you want initialized. I use the Alt + Ins hot-key to access this.
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Selecting multiple classes with jQuery
I’ve had a good look and can’t seem to find out how to select all elements matching certain classes in one jQuery selector statement such as this:
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ERROR ITMS-9000: “Redundant Binary Upload. There already exists a binary upload with build version '
...umber just has to be unique (and higher) for each binary that is uploaded (select the Target, then Xcode -> General -> Build, see the picture below).
For example in the image below the build uploaded has version 3.1.4 (3.75 in the older image) and the build number is 1. Thus, after uploading t...
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...
Multiple file upload in php
... what would the expected outcome be? Browser allowing multiple files to be selected?
– Sven
Oct 3 '12 at 17:41
9
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Compare two files in Visual Studio
... the desktop. That's all!
Usage:
Open the Windows explorer via Win + E
Select two files to compare in the explorer
Drag and drop them as shown in the animation below:
After a few seconds (depending on the launch time of Visual Studio), the results will be shown in Visual Studio:
Note: It d...
How to check if a Constraint exists in Sql server?
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try this:
SELECT
*
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS
WHERE CONSTRAINT_NAME ='FK_ChannelPlayerSkins_Channels'
-- EDIT --
When I originally answered this question, I was thinking "Foreign Key" because the o...
Fastest way to count exact number of rows in a very large table?
I have come across articles that state that SELECT COUNT(*) FROM TABLE_NAME will be slow when the table has lots of rows and lots of columns.
...