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Does MongoDB's $in clause guarantee order
...w the documents are retrieved. That of course will be the natural order or by the selected index order as shown.
If you need to preserve this order, then you basically have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be pas...
Is a view faster than a simple query?
...d, these indexed views can work even when they are not directly referenced by another query as the optimizer will use them in place of a table reference when appropriate.
Again, the documentation:
The indexed view can be used in a query execution in two ways. The query can reference the inde...
iPhone App Icons - Exact Radius?
...2/11 == 57/9 == 6.4 You can take your icon's square length, and divide it by 6.4 to get the same ratio as apple does. So for a 19x19 icon, 19/6.4 ~ 3px border radius
– Devin G Rhode
Jun 14 '11 at 15:57
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Why was “Avoid Enums Where You Only Need Ints” removed from Android's performance tips?
...a bunch of prejudices. it's been rewritten to only contain facts backed up by actual benchmarks, and it's updated as the VM is updated. you can find the various benchmarks -- plus some of the benchmarks we use to optimize the core libraries -- at http://code.google.com/p/dalvik/.
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How do you get assembler output from C/C++ source in gcc?
...erform the initial compilation and then stop before the assembler is run.
By default this will output a file helloworld.s. The output file can be still be set by using the -o option.
gcc -S -o my_asm_output.s helloworld.c
Of course this only works if you have the original source.
An alternative ...
Working with time DURATION, not time of day
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The best way I found to resolve this issue was by using a combination of the above. All my cells were entered as a Custom Format to only show "HH:MM" - if I entered in "4:06" (being 4 minutes and 6 seconds) the field would show the numbers I entered correctly - but the d...
How to configure postgresql for the first time?
...myuser -p <port>
If you don't know the port, you can always get it by running the following, as the postgres user,
SHOW port;
Or,
$ grep "port =" /etc/postgresql/*/main/postgresql.conf
Sidenote: the postgres user
I suggest NOT modifying the postgres user.
It's normally locked from ...
Unnecessary curly braces in C++?
...concerns, variable locality etc.), I use just this technique as elaborated by @unwind.
– ossandcad
Mar 16 '12 at 15:58
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Delete fork dependency of a GitHub repository
...support to switch. Therefore, it is likely that there is no way to do that by yourself (unless you destroy and recreate your repo which is explained before... if you do so be careful if you have tickets or a wiki attached to your project as they will be deleted!).
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Why does Haskell's “do nothing” function, id, consume tons of memory?
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@dfeuer Try asking for the type in ghci. You'll see by the speed of the response that it must be doing the appropriate sharing. I suspect this sharing is lost--for obvious reasons--once you translate to some other intermediate representation (e.g. core).
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