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In MySQL, how to copy the content of one table to another table within the same database?
...y the content of one table to another table within the same database. Basically, I would like to insert to a table from another table. Is there easy way of doing this?
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Is there any advantage of using map over unordered_map in case of trivial keys?
... unordered_map.
Something else to keep in mind is that unordered_map generally uses more memory. map just has a few house-keeping pointers, and memory for each object. Contrarily, unordered_map has a big array (these can get quite big in some implementations), and then additional memory for each ob...
postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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Back to previous page with header( “Location: ” ); in PHP
...this may not work with secure pages (HTTPS) and it's a pretty bad idea overall as the header can be hijacked, sending the user to some other destination. The header may not even be sent by the browser.
Ideally, you will want to either:
Append the return address to the request as a query variable ...
How to search a Git repository by commit message?
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To search the commit log (across all branches) for the given text:
git log --all --grep='Build 0051'
To search the actual content of commits through a repo's history, use:
git grep 'Build 0051' $(git rev-list --all)
to show all instances of the given t...
What's Alternative to Singleton
...singleton in the unit testing because we can test different configurations all at once.
13 Answers
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Is it possible to decompile a compiled .pyc file into a .py file?
... .pyc bytecode into .py, whereas unpyclib crashed with an exception.
With all these tools, you get your code back including variable names, but without the comments.
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Modular multiplicative inverse function in Python
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If you happen to be using sympy, then x, _, g = sympy.numbers.igcdex(a, m) does the trick.
– Lynn
Sep 16 '16 at 18:15
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How to print instances of a class using print()?
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>>> class Test:
... def __repr__(self):
... return "Test()"
... def __str__(self):
... return "member of Test"
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>>> t = Test()
>>> t
Test()
>>> print(t)
member of Test
The __str__ method is what h...
What JSON library to use in Scala? [closed]
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Lift-json is at version 2.6 and it works really well (and is also very well supported, the maintainer is always ready to fix any bugs users may find.
You can find examples using it on the github repository
The maintainer (Joni Freeman) is always reachable on the Lift...