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Copy values from one column to another in the same table
...uestion is:
UPDATE `table` SET test=number
Here table is the table name and it's surrounded by grave accent (aka back-ticks `) as this is MySQL convention to escape keywords (and TABLE is a keyword in that case).
BEWARE, that this is pretty dangerous query which will wipe everything in column te...
Ruby Hash to array of values
...returns [["a", "b", "c"], ["b", "c"]]
Enumerable#collect takes a block, and returns an array of the results of running the block once on every element of the enumerable. So this code just ignores the keys and returns an array of all the values.
The Enumerable module is pretty awesome. Knowing it...
Check if value already exists within list of dictionaries?
...sing the above code can give you a KeyError. You can fix this by using get and providing a default value. If you don't provide a default value, None is returned.
if not any(d.get('main_color', default_value) == 'red' for d in a):
# does not exist
...
How to set std::tuple element by index?
... postfix: "",
imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9....
ARC and bridged cast
...ained <CFType>) op or alternatively CFBridgingRetain(op) is used to hand an NSObject over to CF-land while giving it a +1 retain count. You should handle a CFTypeRef you create this way the same as you would handle a result of CFStringCreateCopy(). This could also be represented by CFRetain((_...
What's wrong with Groovy multi-line String?
... The first assigns test to a, the second two try to make "test" positive (and this is where it fails)
With the new String constructor method, the Groovy parser is still in the constructor (as the brace hasn't yet closed), so it can logically join the three lines together into a single statement
F...
Git: How to return from 'detached HEAD' state
...flog to find the hashes of previously checked out commits.
A shortcut command to get to your last checked out branch (not sure if this work correctly with detached HEAD and intermediate commits though) is git checkout -
sha...
How should I copy Strings in Java?
...e safe. The latter, however, is less efficient (it creates an extra object and in some cases copies the character data).
With this in mind, the first version should be preferred.
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Difference between namespace in C# and package in Java
What is the difference (in terms of use) between namespaces in C# and packages in Java?
6 Answers
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How to get form field's id in Django?
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This answer did not work for me, and Will's above worked perfectly. I tried them back to back with instant feedback.
– eficker
Oct 30 '13 at 21:48
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