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In Postgresql, force unique on combination of two columns
...s you might want a surrogate key to be used as a primary key rather than a combination of columns. In particular to improve performance when doing joins on big data volumes. I personally went for the UNIQUE CONSTRAINT solution below.
– Alexis.Rolland
Jan 13 '19...
Select something that has more/less than x character
...o uses Length.
Here is the Oracle documentation:
http://www.techonthenet.com/oracle/functions/length.php
And here is the mySQL Documentation of Length(string):
http://dev.mysql.com/doc/refman/5.1/en/string-functions.html#function_length
For PostgreSQL, you can use length(string) or char_length(...
Can git automatically switch between spaces and tabs?
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Here is the complete solution:
In your repository, add a file .git/info/attributes which contains:
*.py filter=tabspace
Linux/Unix
Now run the commands:
git config --global filter.tabspace.smudge 'unexpand --tabs=4 --first-only'
g...
C# nullable string error
...e may type string? to tell the world this string may be null. Ref: youtube.com/watch?v=VdC0aoa7ung
– nkalfov
Mar 4 '19 at 23:06
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In C#, how can I create a TextReader object from a string (without writing to disk)
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Sticky and NON-Sticky sessions
...ers A, B and C behind the load balancer, it is possible that www.mywebsite.com/index.jsp is served from server A, www.mywebsite.com/login.jsp is served from server B and www.mywebsite.com/accoutdetails.php are served from server C.
Now, if the requests are being served from (physically) 3 different...
How to disable the application pool idle time-out in IIS7?
... can change this with the DisallowRotationOnConfigChange - see serverfault.com/questions/333907/… for a bit more on that.
– TristanK
Jan 10 '18 at 21:27
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warning: implicit declaration of function
My compiler (GCC) is giving me the warning:
7 Answers
7
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datetime dtypes in pandas read_csv
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This is a slow solution. See this instead: stackoverflow.com/questions/29882573/…
– user1761806
Sep 12 '17 at 14:52
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