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How do I create a unique constraint that also allows nulls?
...er below.
Prior to SQL Server 2008
You cannot create a UNIQUE constraint and allow NULLs. You need set a default value of NEWID().
Update the existing values to NEWID() where NULL before creating the UNIQUE constraint.
s...
When is it acceptable to call GC.Collect?
...ant set of objects - particularly those you suspect to be in generations 1 and 2 - are now eligible for garbage collection, and that now would be an appropriate time to collect in terms of the small performance hit.
A good example of this is if you've just closed a large form. You know that all the...
Errors: “INSERT EXEC statement cannot be nested.” and “Cannot use the ROLLBACK statement within an I
I have three stored procedures Sp1 , Sp2 and Sp3 .
12 Answers
12
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Suppress command line output
... the invocation to this:
taskkill /im "test.exe" /f >nul 2>&1
and all will be better.
That works because stdout is file descriptor 1, and stderr is file descriptor 2 by convention. (0 is stdin, incidentally.) The 2>&1 copies output file descriptor 2 from the new value of 1, whic...
What is makeinfo, and how do I get it?
I'm trying to build GNU grep, and when I run make, I get:
8 Answers
8
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How do I have to configure the proxy settings so Eclipse can download new plugins?
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I had the same problem. I installed Eclipse 3.7 into a new folder, and created a new workspace. I launch Eclipse with a -data argument to reference the new workspace.
When I attempt to connect to the marketplace to get the SVN and Maven plugins, I get the same issues described in OP.
After...
How to get started with developing Internet Explorer extensions?
...previous version of this answer (for Internet Explorer 8, in Windows 7 x64 and Visual Studio 2010) is at the bottom of this answer.
Creating a Working Internet Explorer 11 Add-on
I am using Visual Studio 2017 Community, C#, .Net Framework 4.6.1, so some of these steps might be slightly different f...
Eclipse “Invalid Project Description” when creating new project from existing source
... that project from the source code before, but then I deleted that project and deleted its whole directory, before adding the source code directory again. I tried everything like cleaning and restarting, but nothing worked. I looked in my workspace directory, but there are no traces for the old proj...
Display open transactions in MySQL
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How can I display these open transactions and commit or cancel them?
There is no open transaction, MySQL will rollback the transaction upon disconnect.
You cannot commit the transaction (IFAIK).
You display threads using
SHOW FULL PROCESSLIST
See: http:/...
Declare and Initialize String Array in VBA
...Array( "Cat", "Dog" , "Rabbit"). Variants - yuck!
– Andez
Sep 19 '14 at 10:03
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