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Select count(*) from multiple tables
How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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using awk with column value conditions
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132
If you're looking for a particular string, put quotes around it:
awk '$1 == "findtext" {print...
How do I convert a pandas Series or index to a Numpy array? [duplicate]
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To get a NumPy array, you should use the values attribute:
In [1]: df = pd.DataFrame({'A': [1, 2, 3], 'B': [4, 5, 6]}, index=['a', 'b', 'c']); df
A B
a 1 4
b 2 5
c 3 6
In [2]: df.index.values
Out[2]: array(['a', 'b', 'c'], dtype=object)
This accesses how the data is already ...
Using {} in a case statement. Why?
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195
The {} denotes a new block of scope.
Consider the following very contrived example:
switch (...
Generic List - moving an item within the list
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10 Answers
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How to clone git repository with specific revision/changeset?
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15 Answers
15
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How to undo a git pull?
...plicit than the other answer:
git pull
whoops?
git reset --keep HEAD@{1}
Versions of git older than 1.7.1 do not have --keep. If you use such version, you could use --hard - but that is a dangerous operation because it loses any local changes.
To the commenter
ORIG_HEAD is previous sta...
How to cast int to enum in C++?
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int i = 1;
Test val = static_cast<Test>(i);
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How to rename items in values() in Django?
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edited Jun 20 at 9:12
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answered May 15 '12 at 10:45
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seek() function?
...of reference:
0: means your reference point is the beginning of the file
1: means your reference point is the current file position
2: means your reference point is the end of the file
if omitted, from_what defaults to 0.
Never forget that when managing files, there'll always be a position insi...