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'IF' in 'SELECT' statement - choose output value based on column values
...tp://dev.mysql.com/doc/refman/5.0/en/control-flow-functions.html.
Additionally, you could handle when the condition is null. In the case of a null amount:
SELECT id,
IF(type = 'P', IFNULL(amount,0), IFNULL(amount,0) * -1) as amount
FROM report
The part IFNULL(amount,0) means when amount ...
MySQL - Make an existing Field Unique
...e you don't have duplicates first, no?
– William T. Mallard
Apr 16 '14 at 20:04
1
Be sure to make...
python capitalize first letter only
...rn a titlecased version of S, i.e. words start with title case characters, all remaining cased characters have lower case."
– karantan
Jan 3 '17 at 11:34
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How to make a great R reproducible example
...le examples, see the help files of the function you are using. In general, all the code given there fulfills the requirements of a minimal reproducible example: data is provided, minimal code is provided, and everything is runnable. Also look at questions on Stack Overflow with lots of upvotes.
Pro...
How to go back in Eclipse?
Is there a way to go back in Eclipse? Basically, when I'm jumping around a big project following the execution flow (ctrl + click and etc.), is there a way to retrace a step? If my code calls a method and I go to the method definition, is there a key combination that will take me back to the calling...
Php multiple delimiters in explode
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You can take the first string, replace all the @ with vs using str_replace, then explode on vs or vice versa.
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CSS center display inline block?
...me as I need a child element with display: inline-block to be both horizontally and vertically centered within a 100% width parent.
I used Flexbox's justify-content and align-items properties, which respectively allow you to center elements horizontally and vertically. By setting both to center on...
Return array in a function
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In this case, your array variable arr can actually also be treated as a pointer to the beginning of your array's block in memory, by an implicit conversion. This syntax that you're using:
int fillarr(int arr[])
Is kind of just syntactic sugar. You could really repla...
String output: format or concat in C#?
...le with an existing IL rewriter such as PostSharp.
– Allon Guralnek
Sep 29 '11 at 15:24
31
String...
What's the purpose of git-mv?
From what I understand, Git doesn't really need to track file rename/move/copy operations, so what's the real purpose
of git mv ? The man page isn't specially descriptive...
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