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mkdir -p functionality in Python [duplicate]
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Is there a use-case for singletons with database access in PHP?
...t very often something that you are absolutely sure that you'll never have more than one instance of, you eventually have a second. You may end up with a second monitor, a second database, a second server--whatever.
When this happens, if you have used a static class you're in for a much worse refa...
Throwing exceptions from constructors
...y of doing this. Read this FAQ about Handling a constructor that fails for more information. Having a init() method will also work, but everybody who creates the object of mutex has to remember that init() has to be called. I feel it goes against the RAII principle.
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How to create a zip archive of a directory in Python?
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you may be more interested by doing ziph.write(os.path.join(path,file), arcname=file) so that the filenames inside the archive are not relative to the hard drive
– Christophe Blin
Jun 14 '17 at 7:4...
How to set Oracle's Java as the default Java in Ubuntu?
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Response.Redirect with POST instead of Get?
..., it throws away the POST data, effectively changing 307 redirect into the more common 302.
So, as far as I know, the only way to implement something like this would be to use Javascript. There are two options I can think of off the top of my head:
Create the form and have its action attribute ...
How to open a specific port such as 9090 in Google Compute Engine
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The compute engine has no "networks" option (anymore?)
– Afr
Apr 30 '17 at 14:18
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MySQL - SELECT WHERE field IN (subquery) - Extremely slow why?
... this is notoriously slow.
Only ever use IN with a fixed list of values.
More tips
If you want to make queries faster,
don't do a SELECT * only select
the fields that you really need.
Make sure you have an index on relevant_field to speed up the equi-join.
Make sure to group by on the primary ...
What does (x ^ 0x1) != 0 mean?
... don't know the context. If x is some kind of bit flag, it is IMO actually more clear to write it as it is now than using the != operator.
– Spook
Dec 19 '13 at 10:57
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Truncating floats in Python
... would come up with 0.2 even though that's probably not what you want. For more on floating-point representation error, see the Python tutorial.
It's very rare to be working with a floating-point value that is so close to a round number and yet is intentionally not equal to that round number. So wh...