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When should I use a composite index?
..._C )
will benefit a query that uses those fields for joining, filtering, and sometimes selecting. It will also benefit queries that use left-most subsets of columns in that composite. So the above index will also satisfy queries that need
index( column_A, column_B, column_C )
index( column_A, col...
Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
Simple question really; is there a difference between these values (and is there a difference between BOOL and bool)? A co-worker mentioned that they evaluate to different things in Objective-C, but when I looked at the typedefs in their respective .h files, YES/TRUE/true were all defined as 1 an...
How can I return pivot table output in MySQL?
...w.artfulsoftware.com/infotree/qrytip.php?id=78
I advise reading this post and adapt this solution to your needs.
Update
After the link above is currently not available any longer I feel obliged to provide some additional information for all of you searching for mysql pivot answers in here. It rea...
“tag already exists in the remote" error after recreating the git tag
...o get everyone who already has the "wrong" tag to delete their "wrong tag" and replace it with the new "right tag".
Testing in Git 2.10/2.11 shows that retaining the old tag is the default behavior for clients running git fetch, and updating is the default behavior for clients running git fetch --t...
How to enable local network users to access my WAMP sites?
First of all, I read at least 20 articles about this topic, and not one of them can match up the scenario and I screwed up the process numerous times. So I turn help by offering my specific scenario if any help will be appreciated.
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How to split a string and assign it to variables
In Python it is possible to split a string and assign it to variables:
9 Answers
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Return a value if no rows are found in Microsoft tSQL
...1) > 0 THEN 1 ELSE 0 END AS [Value]
FROM Sites S
WHERE S.Id = @SiteId and S.Status = 1 AND
(S.WebUserId = @WebUserId OR S.AllowUploads = 1)
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What is the “right” way to iterate through an array in Ruby?
...arts, is pretty good on this count. There's no difference between an array and a hash (maybe I'm naive, but this seems obviously right to me), and to iterate through either you just do
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What is the difference between exit(0) and exit(1) in C?
Can anyone tell me? What is the difference between exit(0) and exit(1) in C language?
11 Answers
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What's the difference between “mod” and “remainder”?
My friend said that there are differences between "mod" and "remainder".
5 Answers
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