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Which is faster: Stack allocation or Heap allocation
...heap allocated memory
– Benoît
Apr 10 '09 at 10:29
49
On some (mostly embedded, that I know of) ...
What is simplest way to read a file into String? [duplicate]
...ver-complicated. I agree however that using another lib just for this is a bit overkill.
– Andrea Lazzarotto
Aug 18 '14 at 9:21
3
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Why is string concatenation faster than array join?
... is that this slows down other operations on the resulting string a little bit. Also this of course reduces memory overhead.
On the other hand ['abc', 'def'].join('') would usually just allocate memory to lay out the new string flat in memory. (Maybe this should be optimized)
...
Difference between variable declaration syntaxes in Javascript (including global variables)?
...e it's only in passing, you won't find a browser that doesn't do it. I'm a bit surprised it's not in Annex B.
– T.J. Crowder
Apr 3 '16 at 7:23
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Do I cast the result of malloc?
... differently sized; then you're hiding a warning by casting and might lose bits of your returned address. Note: as of C99 implicit functions are gone from C, and this point is no longer relevant since there's no automatic assumption that undeclared functions return int.
As a clarification, note th...
MySQL “WITH” clause
...QL:1999's various features on Wikipedia.
MySQL has traditionally lagged a bit in support for the SQL standard, whereas commercial databases like Oracle, SQL Server (recently), and DB2 have followed them a bit more closely. PostgreSQL is typically pretty standards compliant as well.
You may want to...
Disable all table constraints in Oracle
...constraint_name);
END LOOP;
END;
/
Enabling the constraints again is a bit tricker - you need to enable primary key constraints before you can reference them in a foreign key constraint. This can be done using an ORDER BY on constraint_type. 'P' = primary key, 'R' = foreign key.
BEGIN
FOR ...
Difference between Java Enumeration and Iterator
...
I think there is a bit of explanation missing from this answer regarding concurrency.
– Maarten Bodewes
Jul 24 '12 at 16:01
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Drop data frame columns by name
...prasad, see @joris answer below. A subset without any subset criteria is a bit of overkill. Try simply: df[c("a", "c")]
– JD Long
Jan 5 '11 at 15:16
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How to initialize static variables
...class loader doesn't make it go away, forces false inheritance, and it's a bit of cleverness that could unexpectedly break (e.g. when file is require()d explicitly).
– Kornel
Aug 8 '13 at 2:39
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