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MySQL - why not index every field?
Recently I've learned the wonder of indexes, and performance has improved dramatically. However, with all I've learned, I can't seem to find the answer to this question.
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What is an application binary interface (ABI)?
...an ABI is. Please don't point me to a Wikipedia article. If I could understand it, I wouldn't be here posting such a lengthy post.
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Is there a NumPy function to return the first index of something in an array?
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Yes, here is the answer given a NumPy array, array, and a value, item, to search for:
itemindex = numpy.where(array==item)
The result is a tuple with first all the row indices, then all the column indices.
For example, if an array is two dimensions and it contained your it...
_csv.Error: field larger than field limit (131072)
... csv
csv.field_size_limit(sys.maxsize)
sys.maxsize works for Python 2.x and 3.x. sys.maxint would only work with Python 2.x (SO: what-is-sys-maxint-in-python-3)
Update
As Geoff pointed out, the code above might result in the following error: OverflowError: Python int too large to convert to C l...
Installing pip packages to $HOME folder
...This should result in the hg script being installed in $HOME/.local/bin/hg and the rest of the hg package in $HOME/.local/lib/pythonx.y/site-packages/.
Note, that the above is true for Python 2.6. There has been a bit of controversy among the Python core developers about what is the appropriate di...
How to concatenate two strings in C++?
...e performance. Worst case is, that operator+= performs both a deallocation and an allocation. Heap allocations are among the most expensive operations we commonly do.
– IInspectable
Feb 7 at 12:17
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How do I show multiple recaptchas on a single page?
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A similar question was asked about doing this on an ASP page (link) and the consensus over there was that it was not possible to do with recaptcha. It seems that multiple forms on a single page must share the captcha, unless you're willing to use a different captcha. If you are not locked int...
Git Bash doesn't see my PATH
... wasn't able to run the file though, since apparently bash couldn't understand its contents)
One more reason to switch to posh-git..
Thanks @Tom for pointing me to the right direction.
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Proper stack and heap usage in C++?
I've been programming for a while but It's been mostly Java and C#. I've never actually had to manage memory on my own. I recently began programming in C++ and I'm a little confused as to when I should store things on the stack and when to store them on the heap.
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Optimise PostgreSQL for fast testing
.... For example, PostgreSQL 9.2 significantly improves the speed of TRUNCATE and of course adds index-only scans. Even minor releases should always be followed; see the version policy.
Don'ts
Do NOT put a tablespace on a RAMdisk or other non-durable storage.
If you lose a tablespace the whole datab...