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How do I execute a stored procedure once for each row returned by query?
...stored procedure that alters user data in a certain way. I pass it user_id and it does it's thing. I want to run a query on a table and then for each user_id I find run the stored procedure once on that user_id
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Fast way to discover the row count of a table in PostgreSQL
...IN pg_namespace n ON n.oid = c.relnamespace
WHERE c.relname = 'mytable'
AND n.nspname = 'myschema'
Or better still
SELECT reltuples::bigint AS estimate
FROM pg_class
WHERE oid = 'myschema.mytable'::regclass;
Faster, simpler, safer, more elegant. See the manual on Object Identifier Type...
Ruby: require vs require_relative - best practice to workaround running in both Ruby =1.
What is the best practice if I want to require a relative file in Ruby and I want it to work in both 1.8.x and >=1.9.2?
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What is the difference between getFields and getDeclaredFields in Java reflection
I'm a little confused about the difference between the getFields method and the getDeclaredFields method when using Java reflection.
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Why is argc not a constant?
...this case, history is a factor. C defined these inputs as "not constant", and compatibility with (a good portion of) existing C code was an early goal of C++.
Some UNIX APIs, such as getopt, actually do manipulate argv[], so it can't be made const for that reason also.
(Aside: Interestingly, al...
What is a git topic branch?
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Topic branches are typically lightweight branches that you create locally and that have a name that is meaningful for you. They are where you might do work for a bug fix or feature (they're also called feature branches) that is expected to take some time to complete.
Another type of branch is the ...
Is it possible to run JavaFX applications on iOS, Android or Windows Phone 8?
Can one develop an entire application using JavaFX and run it on iOS, Android or Windows Phone 8, without writing platform-specific code?
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Why does the indexing start with zero in 'C'?
Why does the indexing in an array start with zero in C and not with 1?
16 Answers
16
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Python `if x is not None` or `if not x is None`?
...he if not x is None version to be more clear, but Google's style guide and PEP-8 both use if x is not None . Is there any minor performance difference (I'm assuming not), and is there any case where one really doesn't fit (making the other a clear winner for my convention)?*
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What does 'wb' mean in this code, using Python?
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File mode, write and binary. Since you are writing a .jpg file, it looks fine.
But if you supposed to read that jpg file you need to use 'rb'
More info
On Windows, 'b' appended to the mode
opens the file in binary mode, so
there ar...