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MongoDB SELECT COUNT GROUP BY
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I need some extra operation based on the result of aggregate function. Finally I've found some solution for aggregate function and the operation based on the result in MongoDB. I've a collection Request with field request, source, status, requestDate.
Single Field Group By & Count:
db.Request...
Delete files older than 10 days using shell script in Unix [duplicate]
... these! Once, using a command very much like this in a cron job, I accidentally deleted every file on my production mail server older than 10 days, which I can tell you was no fun to recover from.
– DSimon
May 28 '14 at 20:00
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Best way to strip punctuation from a string
...s working with the same datatype, but the approach in this answer works equally well for both, which is handy.
– Richard J
Jan 16 '15 at 9:35
38
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How to efficiently count the number of keys/properties of an object in JavaScript?
...t only iterates through the object but also creates a whole new array with all its keys, so it completely fails at answering the question.
– GetFree
Jun 22 '12 at 14:28
43
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How to throw an exception in C?
...and caught in the program, but the C code portions will remain ignorant of all of this going on except that exception throwing and catching often rely on functions written in C which reside in the C++ libraries. C is used because you can't risk the function called to do throw needing to throw an exc...
Python: most idiomatic way to convert None to empty string?
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If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
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How do I import the Django DoesNotExist exception?
...y of the model itself, in this case Answer.
Your problem is that you are calling the get method - which raises the exception - before it is passed to assertRaises. You need to separate the arguments from the callable, as described in the unittest documentation:
self.assertRaises(Answer.DoesNotExis...
What does the C++ standard state the size of int, long type to be?
... value of the CHAR_BIT macro that defines the number of bits in a byte. In all but the most obscure platforms it's 8, and it can't be less than 8.
One additional constraint for char is that its size is always 1 byte, or CHAR_BIT bits (hence the name). This is stated explicitly in the standard.
The C...
How to use the TextWatcher class in Android?
...ich are overridden for the text watcher. you can mask the text which you really wanted to.
– Dinesh Prajapati
Dec 17 '11 at 8:07
2
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Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...