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SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
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Without the update-and-join notation (not all DBMS support that), use:
UPDATE QuestionTrackings
SET QuestionID = (SELECT QuestionID
FROM AnswerTrackings
WHERE AnswerTrackings.AnswerID = QuestionTrackings.AnswerID)
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Any way to replace characters on Swift String?
...n leaves me with and optional string. Original String looks like this: "x86_64" and the new mapping looks like "Optional([\"x\", \"8\", \"6\", \"_\", \"6\", \"4\"])"
– John Shelley
Oct 19 '15 at 15:07
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Fast way of counting non-zero bits in positive integer
...nt() took about 1/20th of the time of bin(n).count("1"). So if you can install gmpy, use that.
To answer a question in the comments, for bytes I'd use a lookup table. You can generate it at runtime:
counts = bytes(bin(x).count("1") for x in range(256)) # py2: use bytearray
Or just define it lit...
What is “callback hell” and how and why does RX solve it?
... clear definition together with a simple example that explains what is a "callback hell" for someone who does not know JavaScript and node.js ?
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Can you call Directory.GetFiles() with multiple filters?
...er,
var files = Directory.EnumerateFiles("C:\\path", "*.*", SearchOption.AllDirectories)
.Where(s => s.EndsWith(".mp3") || s.EndsWith(".jpg"));
For earlier versions of .NET,
var files = Directory.GetFiles("C:\\path", "*.*", SearchOption.AllDirectories)
.Where(s => ...
passport.js passport.initialize() middleware not in use
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I keep getting this exception after authentication success (I see the callback url on the browser):
7 Answers
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Python Create unix timestamp five minutes in the future
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Now in Python >= 3.3 you can just call the timestamp() method to get the timestamp as a float.
import datetime
current_time = datetime.datetime.now(datetime.timezone.utc)
unix_timestamp = current_time.timestamp() # works if Python >= 3.3
unix_timestamp_pl...
Creating anonymous objects in php
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This is interesting but it doesn't really address the question, as the OP was asking about a convenient way to initialise an object with various members without creating a class. I am not sure whether anonymous classes in php can be used to do that, and if it ca...
How to get the concrete class name as a string? [duplicate]
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instance.__class__.__name__
example:
>>> class A():
pass
>>> a = A()
>>> a.__class__.__name__
'A'
share
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How to perform a mysqldump without a password prompt?
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Since you are using Ubuntu, all you need to do is just to add a file in your home directory and it will disable the mysqldump password prompting. This is done by creating the file ~/.my.cnf (permissions need to be 600).
Add this to the .my.cnf file
[m...