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Is there ever a time where using a database 1:1 relationship makes sense?
...n, and it occurred to me, I cannot think of a time where there should be a 1:1 relationship in a database.
26 Answers
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Programmatically obtain the Android API level of a device?
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You can obtain API level programatically by the system constant (Build.VERSION.SDK_INT). For e...
Python and pip, list all versions of a package that's available?
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16 Answers
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How to find list intersection?
actual output: [1,3,5,6]
expected output: [1,3,5]
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What is the bower (and npm) version syntax?
...example: to indicate you'll take any subsequent patch-level changes on the 1.2.x tree, starting with 1.2.0, but less than 1.3.0, you could use:
"angular": "~1.2"
or:
"angular": "~1.2.0"
This also gets you the same results as using the .x syntax:
"angular": "1.2.x"
But, you can use the tilde...
How do I check to see if a value is an integer in MySQL?
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Fast permutation -> number -> permutation mapping algorithms
I have n elements. For the sake of an example, let's say, 7 elements, 1234567. I know there are 7! = 5040 permutations possible of these 7 elements.
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Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
...gation methods at once. This should give you the result you need:
df[['col1', 'col2', 'col3', 'col4']].groupby(['col1', 'col2']).agg(['mean', 'count'])
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How to count the frequency of the elements in an unordered list?
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