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How to drop into REPL (Read, Eval, Print, Loop) from Python code
Is there a way to programmatically force a Python script to drop into a REPL at an arbitrary point in its execution, even if the script was launched from the command line?
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How to count occurrences of a column value efficiently in SQL?
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This should work:
SELECT age, count(age)
FROM Students
GROUP by age
If you need the id as well you could include the above as a sub query like so:
SELECT S.id, S.age, C.cnt
FROM Students S
INNER JOIN (SELECT age, count(age) as cnt
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Creating an official github mirror
How do I create a github mirror for an external git repository, such that it appears as "real mirror", e.g., as in https://github.com/mirrors ?
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How to see full symlink path
When I'm using ls -la symlinkName or stat symlinkName not all the path is displayed
(e.g ../../../one/two/file.txt )
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Efficiency of purely functional programming
Does anyone know what is the worst possible asymptotic slowdown that can happen when programming purely functionally as opposed to imperatively (i.e. allowing side-effects)?
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What is the difference between gmake and make?
I am trying to understand the difference between 'gmake' and 'make'?
4 Answers
4
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When does static class initialization happen?
... but I access a static field, are ALL the static blocks and private static methods used to instantiate private static fields called (in order) at that instant?
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Django in / not in query
I'm trying to figure out how to write a 'not in' style query in django.
For example, the query structure I'm thinking of would look like this.
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What is the maximum depth of the java call stack?
...nto the call stack before I get a StackOverflowError? Is the answer platform dependent?
4 Answers
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Using Vim's persistent undo?
One of the new features in Vim 7.3 is 'persistent undo', which allows for the undotree to be saved to a file when exiting a buffer.
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