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Multiple select statements in Single query
I am generating a report in php (mysql),
6 Answers
6
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Using property() on classmethods
... (using the classmethod() function) for getting and setting what is essentially a static variable. I tried to use the property() function with these, but it results in an error. I was able to reproduce the error with the following in the interpreter:
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Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...
MPICH vs OpenMPI
...xtensive optimizations that make it the preferred implementation in nearly all cases.
Feature Support from the Latest MPI Standard
An orthogonal axis to hardware/platform support is coverage of the MPI standard. Here MPICH is usually far and away superior. MPICH has been the first implementation...
What is the formal difference in Scala between braces and parentheses, and when should they be used?
...ut this, but I gave up in the end, as the rules are somewhat diffuse. Basically, you’ll have to get the hang of it.
Perhaps it is best to concentrate on where curly braces and parenthesis can be used interchangeably: when passing parameters to method calls. You may replace parenthesis with curly b...
Pandas selecting by label sometimes return Series, sometimes returns DataFrame
...answered Dec 4 '13 at 19:36
Dan AllanDan Allan
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How to send a “multipart/form-data” with requests in python?
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Basically, if you specify a files parameter (a dictionary), then requests will send a multipart/form-data POST instead of a application/x-www-form-urlencoded POST. You are not limited to using actual files in that dictionary, howe...
How to create REST URLs without verbs?
I'm struggling to determine how to design restful URLs. I'm all for the restful approach of using URLs with nouns and not verbs don't understand how to do this.
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Django filter queryset __in for *every* item in list
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Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...
Why aren't python nested functions called closures?
...s in Python, and they match the definition of a closure. So why are they called nested functions instead of closures ?
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