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Why is LINQ JOIN so much faster than linking with WHERE?
...ite efficient because the DB knows how to perform a join. But it doesn't really make sense to compare it with the other approaches, since they work directly in memory (Linq to DataSet)
The query with multiple tables and a Where condition actually performs a cartesian product of all the tables, then ...
How to find the width of a div using vanilla JavaScript?
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All Answers are right, but i still want to give some other alternatives that may work.
If you are looking for the assigned width (ignoring padding, margin and so on) you could use.
getComputedStyle(element).width; //returns...
How can I mock requests and the response?
...thons mock package to mock Pythons requests module. What are the basic calls to get me working in below scenario?
9 Answ...
Loop backwards using indices in Python?
... This is better than the accepted answer since it doesn't actually allocate all the numbers in memory (in Python 3 the accepted answer wouldn't either), plus it's more obvious what is happening.
– Blixt
Mar 23 '12 at 13:52
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Javascript equivalent of Python's zip function
..., unlike Python's version where the argument list is variadic. If you want all of these "features", see below. It takes just about 2 extra lines of code.
The following will mimic Python's zip behavior on edge cases where the arrays are not of equal size, silently pretending the longer parts of arra...
Why are only a few video games written in Java? [closed]
...d port it, that takes a lot of effort (and of course, the license needs to allow it).
Also, a lot of legacy code already exists in C++. If code from previous projects can be reused (say, if you're writing a sequel), that counts even more in favor of sticking with the same language, instead of rewri...
Storing Images in DB - Yea or Nay?
...tabase to be best.
There are a couple of issues:
database storage is usually more expensive than file system storage
you can super-accelerate file system access with standard off the shelf products
for example, many web servers use the operating system's sendfile() system call to asynchronously...
How do you serialize a model instance in Django?
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You can easily use a list to wrap the required object and that's all what django serializers need to correctly serialize it, eg.:
from django.core import serializers
# assuming obj is a model instance
serialized_obj = serializers.serialize('json', [ obj, ])
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How to make a valid Windows filename from an arbitrary string?
...: Bar" that I want to use as a filename, but on Windows the ":" char isn't allowed in a filename.
14 Answers
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MySQL, Check if a column exists in a table with SQL
...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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