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How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
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@dev_feed In terms of database design I don't see the link back to be beneficial, but using the example above the link back could simplify finding a student given an address.
– edhedges
Sep 6 '14 at 23:23
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WebRTC vs Websockets: If WebRTC can do Video, Audio, and Data, why do I need Websockets? [closed]
...peer protocol. It's starting to see widespread use in industry as a server-based VOIP alternative.
– photicSphere
Jan 31 '18 at 0:42
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Rename specific column(s) in pandas
...is argument was introduced in v0.21.
Index.str.replace() for string/regex based replacement.
If you need to rename ALL columns at once,
DataFrame.set_axis() method with axis=1. Pass a list-like sequence. Options are available for in-place modification as well.
rename with axis=1
df = pd.DataFr...
How does this milw0rm heap spraying exploit work?
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In this case it was not a heap corruption, heap-based buffer overrun or stack-based buffer overrun: blogs.msdn.com/sdl/archive/2008/12/18/ms08-078-and-the-sdl.aspx
– Grant Wagner
Dec 19 '08 at 16:19
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Nohup is not writing log to output file
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python as well as other C stdio-based programs uses line-buffering in interactive case (stdout is connected to a tty) and block-buffering when redirected to a file. If python -u doesn't work; nohup might have introduced its own buffering.
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Why does sun.misc.Unsafe exist, and how can it be used in the real world?
...tiated by sun.misc.Unsafe, useful for instrumentation
sun.misc.Unsafe.arrayBaseOffset and arrayIndexScale can be used to develop arraylets,a technique for efficiently breaking up large arrays into smaller objects to limit the real-time cost of scan, update or move operations on large objects
http://...
Where does PostgreSQL store the database?
Where are the files for a PostgreSQL database stored?
13 Answers
13
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How to check if a column exists in Pandas
...ments, you can use the get() method for DataFrames. For performing the sum based on the question:
df['sum'] = df.get('A', df['B']) + df['C']
The DataFrame get method has similar behavior as python dictionaries.
share
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how to unit test file upload in django
...ation test -- doesn't actually matter until you get into more complex code bases maybe even with an actual test team
– Alvin
May 2 '17 at 18:49
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Relative URL to a different port number in a hyperlink?
... For instance this modified code just worked for me and moves me from any base port to port 8069 (replace your port as required)
<div>
<a href="http://<?php print
$_SERVER{'SERVER_NAME'}; ?>:8069"><img
src="images/example.png"/>Example Base (http)</a>
<...