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Swapping column values in MySQL
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answered Feb 18 '09 at 0:01
Artem RussakovskiiArtem Russakovskii
19.7k1717 gold badges8686 silver badges114114 bronze badges
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Direct vs. Delegated - jQuery .on()
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What is HEAD in Git?
... @Meng This one helped me, hope it helps: marklodato.github.com/visual-git-guide/index-en.html
– raphael
Jan 4 '12 at 18:49
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Using i and j as variables in Matlab
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Because i and j are both functions denoting the imaginary unit:
http://www.mathworks.co.uk/help/matlab/ref/i.html
http://www.mathworks.co.uk/help/matlab/ref/j.html
So a variable called i or j will override them, potentially silently breaking code that does complex maths.
Possible solutions in...
Postgres: INSERT if does not exist already
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Postgres 9.5 (released since 2016-01-07) offers an "upsert" command, also known as an ON CONFLICT clause to INSERT:
INSERT ... ON CONFLICT DO NOTHING/UPDATE
It solves many of the subtle problems you can run into when using concurrent operation, which some other answers propose.
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Can I use CASE statement in a JOIN condition?
...END = 1
Note that you need to do something with the returned value, e.g. compare it to 1. Your statement attempted to return the value of an assignment or test for equality, neither of which make sense in the context of a CASE/THEN clause. (If BOOLEAN was a datatype then the test for equality wo...
Get current AUTO_INCREMENT value for any table
... Note: DATABASE() is NULL if you have not issued a USE DATABASE command
– methai
Apr 5 '13 at 14:13
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What is the best way to use a HashMap in C++?
... you don't know how to do this, GeeksforGeeks has a great tutorial https://www.geeksforgeeks.org/operator-overloading-c/
Under the standard namespace, declare a template struct called hash with your classname as the type (see below). I found a great blogpost that also shows an example of calculating...
How to scale an Image in ImageView to keep the aspect ratio
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edited Jun 20 at 9:12
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111 silver badge
answered Mar 26 '10 at 15:07
Steve HaleySteve Ha...
Rank items in an array using Python/NumPy, without sorting array twice
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any recommendation on how to do this rowwise?
– Xaser
Nov 19 '17 at 14:09
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