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How do I find a stored procedure containing ?
... A million times what @PeteT said. This 4000 character limit really bit me a few years ago.
– Vivian River
Mar 31 '15 at 17:40
16
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cartesian product in pandas
...n unused column name, then add dummy columns with that name, merge, and finally drop the column on the result? Creating, as opposed to reading, data with pandas is just a pain
– Bananach
Oct 10 '19 at 7:31
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How to import classes defined in __init__.py
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wow, the word "helper" really starts to loose meaning in that example. However, you've shown me what I was looking for.
– scottm
Feb 24 '09 at 21:06
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How to programmatically set style attribute in a view
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Generally you can't change styles programmatically; you can set the look of a screen, or part of a layout, or individual button in your XML layout using themes or styles. Themes can, however, be applied programmatically.
There i...
MySQL SELECT only not null values
...hough...
SELECT val1 AS val
FROM your_table
WHERE val1 IS NOT NULL
UNION ALL
SELECT val2
FROM your_table
WHERE val2 IS NOT NULL
/*And so on for all your columns*/
The disadvantage of the above is that it scans the table multiple times once for each column. That may possibly be avoided by the b...
Suppress/ print without b' prefix for bytes in Python 3
...daausdaau
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Is there an ignore command for git like there is for svn?
... .git/info/exclude file will not be committed, and will thus only apply locally in this one working copy.
You can also set up a global file with patterns to ignore with git config --global core.excludesfile. This will locally apply to all git working copies on the same user's account.
Run git help...
What is a simple command line program or script to backup SQL server databases?
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There's a good script to backup all user databases in one go here: mssqltips.com/tip.asp?tip=1070
– Marnix van Valen
Sep 22 '09 at 14:47
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What is the easiest way to initialize a std::vector with hardcoded elements?
I can create an array and initialize it like this:
29 Answers
29
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if A vs if A is not None:
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The statement
if A:
will call A.__nonzero__() (see Special method names documentation) and use the return value of that function. Here's the summary:
object.__nonzero__(self)
Called to implement truth value testing and the built-in operation ...