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postgresql - add boolean column to table set default
...D COLUMN priv_user BOOLEAN;, then UPDATE users SET priv_user = 'f'; and finally if you need to ALTER TABLE users ALTER COLUMN priv_user SET NOT NULL;.
– Craig Ringer
Aug 14 '12 at 0:19
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Can TCP and UDP sockets use the same port?
First of all, is there any problem with using both UDP and TCP on the same server?
2 Answers
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How to easily initialize a list of Tuples?
I love tuples . They allow you to quickly group relevant information together without having to write a struct or class for it. This is very useful while refactoring very localized code.
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Split string based on a regular expression
...y in this case.
>>> str1.split()
['a', 'b', 'c', 'd']
If you really wanted regex you can use this ('\s' represents whitespace and it's clearer):
>>> re.split("\s+", str1)
['a', 'b', 'c', 'd']
or you can find all non-whitespace characters
>>> re.findall(r'\S+',str1)
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NumPy array initialization (fill with identical values)
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On my system (Python 2.7, Numpy 1.8), np.full() is actually slightly slower than np.empty() followed by np.fill().
– John Zwinck
Jul 25 '14 at 8:37
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Calc of max, or max of calc in CSS
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min(), max(), and clamp() are finally available!
Starting in Firefox 75, Chrome 79, and Safari 11.1 (except clamp).
min() and max() take any number of arguments.
clamp() has syntax clamp(MIN, VAL, MAX) and is equivalent to max(MIN, min(VAL, MAX)).
min() ...
Is there a destructor for Java?
...re is no direct equivalent of a destructor.
There is an inherited method called finalize, but this is called entirely at the discretion of the garbage collector. So for classes that need to explicitly tidy up, the convention is to define a close method and use finalize only for sanity checking (i.e...
SQL command to display history of queries
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try
cat ~/.mysql_history
this will show you all mysql commands ran on the system
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How to 'insert if not exists' in MySQL?
... any AUTO_INCREMENT column with failed insert. Probably because it's not really failed, but UPDATE'd.
– not2qubit
Oct 29 '13 at 21:36
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How to remove the first commit in git?
...med reference HEAD, so it will reset (softly, you will not lose your work) all your commits of your current branch.
If what you want is to merge the first commit with the second one, you can use the rebase command:
git rebase -i --root
A last way could be to create an orphan branch, a branch wit...