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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 ...
'const string' vs. 'static readonly string' in C#
...e private const for values that aren't, strictly speaking, constants; basically it's misusing const for micro-optimisation purposes. I'm going to stand by my "never, ever, ever" statement, even if it makes me a hypocrite. ;)
– LukeH
Nov 18 '12 at 1:32
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When to use pip requirements file versus install_requires in setup.py?
I'm using pip with virtualenv to package and install some Python libraries.
4 Answers
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LINQ .Any VS .Exists - What's the difference?
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I later made a post in another thread where I listed all the Linq "equivalents" of the .NET 2 List<> instance methods.
– Jeppe Stig Nielsen
Dec 1 '15 at 8:44
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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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What is the Git equivalent for revision number?
...e SVN at work, but for my personal projects I decided to use Git. So I installed Git yesterday, and I wonder what is the revision number equivalent in Git .
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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...
Why would you use String.Equals over ==? [duplicate]
I recently was introduced to a large codebase and noticed all string comparisons are done using String.Equals() instead of ==
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