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How can I convert immutable.Map to mutable.Map in Scala?
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: _* is much like type ascription, telling the compiler exactly what type to asign to a given expression. You can think of it here as saying "take this sequence, and treat it as a number of vararg params."
– Kevin Wright
Jun 6 '12 a...
Efficiently updating database using SQLAlchemy ORM
... you say
for c in session.query(Stuff).all():
c.foo = c.foo+1
session.commit()
it will do what it says, go fetch all the objects from the database, modify all the objects and then when it's time to flush the changes to the database, update the rows one by one.
Instead you should do this:
se...
Do declared properties require a corresponding instance variable?
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add a comment
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How to “git clone” including submodules?
...d instead of --recursive:
git clone --recurse-submodules -j8 git://github.com/foo/bar.git
cd bar
Editor’s note: -j8 is an optional performance optimization that became available in version 2.8, and fetches up to 8 submodules at a time in parallel — see man git-clone.
With version 1.9 of Git ...
Segmentation fault on large array sizes
...k because it's specified as an array with a constant number of elements at compile time. Values are only put on the heap with malloc, new, etc.
– Seth Johnson
Dec 4 '09 at 16:05
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What are naming conventions for MongoDB?
... See this question for the single vs plural debate: stackoverflow.com/questions/338156/…
– Jason
Apr 21 '16 at 7:31
5
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How many socket connections can a web server handle?
... I couldn't resist answering myself, many answers to the question here are completely incorrect.
Best Case
The answer to this question must only concern itself with the simplest server configuration to decouple from the countless variables and configurations possible downstream.
So consider the foll...
Multiple INSERT statements vs. single INSERT with multiple VALUES
I'm running a performance comparison between using 1000 INSERT statements:
4 Answers
4...