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SQL Server insert if not exists best practice
I have a Competitions results table which holds team member's names and their ranking on one hand.
8 Answers
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Fully backup a git repo?
Is there a simple way to backup an entire git repo including all branches and tags?
13 Answers
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What are fixtures in programming?
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The purpose of a test fixture is to ensure that there is a well known
and fixed environment in which tests are run so that results are
repeatable. Some people call this the test context.
Examples of fixtures:
Loading a database with a specific, known set of data
Erasing a hard ...
“Insert if not exists” statement in SQLite
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If you have a table called memos that has two columns id and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where ...
Check if passed argument is file or directory in Bash
...n Ubuntu which would allow me to pass it either a filename or a directory, and be able to do something specific when it's a file, and something else when it's a directory. The problem I'm having is when the directory name, or probably files too, has spaces or other escapable characters are in the n...
In MySQL what does “Overhead” mean, what is bad about it, and how to fix it?
...x paths, defragmenting, etc. is
what is known as OPTIMIZATION in mysql
and other terms in other databases.
For example, IBM DB2/400 calls it
REORGANIZE PHYSICAL FILE MEMBER.
It's kind of like changing the oil in
your car or getting a tune-up. You may
think you really don't have to, ...
Fastest way to determine if record exists
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@Declan_K: seems like my magic sphere failed in this case and a column entitled as id isn't PK. So +1 to your advice.
– zerkms
Aug 7 '13 at 22:00
4
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Is < faster than
...n two machine instructions:
A test or cmp instruction, which sets EFLAGS
And a Jcc (jump) instruction, depending on the comparison type (and code layout):
jne - Jump if not equal --> ZF = 0
jz - Jump if zero (equal) --> ZF = 1
jg - Jump if greater --> ZF = 0 and SF = OF
(etc...)
Exa...
What is the difference between IQueryable and IEnumerable?
What is the difference between IQueryable<T> and IEnumerable<T> ?
13 Answers
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Should JAVA_HOME point to JDK or JRE?
...\Program Files (x86)\Java\jre7 . It works fine. Afterwards, I unzipped ant and set up the environment variables related to Ant, I got the following error messages after typing "ant -version"
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