大约有 37,000 项符合查询结果（耗时：0.0529秒） [XML]
Right query to get the current number of connections in a PostgreSQL DB
...
Those two requires aren't equivalent. The equivalent version of the first one would be:
SELECT sum(numbackends) FROM pg_stat_database;
In that case, I would expect that version to be slightly faster than the second one, simp...
Reducing MongoDB database file size
...dTiger it looks like the extra disk space will actually be released to the OS.
UPDATE: as of v1.9+ there is a compact command.
This command will perform a compaction "in-line". It will still need some extra space, but not as much.
MongoDB compresses the files by:
copying the files to a new ...
Combining multiple git repositories
...ackup of your phd directory: I don't want to be held responsible for your losing years of hard work! ;-)
$ cp -r phd phd-backup
Move the content of phd/code to phd/code/code, and fix the history so that it looks like it has always been there (this uses git's filter-branch command):
$ cd phd/code...
How do I print the full value of a long string in gdb?
... This answer is even better than "set print elements 0" (for my purposes) because it respects the newline/carriage return chars instead of escaping them.
– mhenry1384
Jun 22 '10 at 16:34
...
Garbage collector in Android
... then improves things, performance-wise. This is because it is not really possible to implement a "perfect" GC which will manage memory optimally in all cases. Such situations are hard to predict and depend on many subtle implementation details. The "good practice" is to let the GC run by itself; a ...
How do you run a command for each line of a file?
...r example, right now I'm using the following to change a couple of files whose Unix paths I wrote to a file:
9 Answers
...
RVM is not working in ZSH
.../rvm" ]] && . "$HOME/.rvm/scripts/rvm" is in my .zlogin, but I suppose it wasn't using it when opening new terminal windows on my mac (10.7.3, oh my zsh). Adding it to the .zshrc worked for me too but according to this stackoverflow comment, .zshrc is the wrong place to put this??
...
Explanation of JSHint's Bad line breaking before '+' error
...s format? To me it has the edge in scannability.
– HostileFork says dont trust SE
Mar 20 '15 at 1:47
|
show 6 more comments
...
How to detect Windows 64-bit platform with .NET?
...-bit .NET Framework 2.0 on 64-bit Windows (it would return 32-bit).
As Microsoft's Raymond Chen describes, you have to first check if running in a 64-bit process (I think in .NET you can do so by checking IntPtr.Size), and if you are running in a 32-bit process, you still have to call the Win API fu...
How to use Active Support core extensions
...t/core_ext/object/blank'
If you don't care about granularity, you can choose to load bigger chunks. If you want everything in one big gulp use...
For 1.9.2:
rvm 1.9.2
irb -f
irb(main):001:0> require 'active_support/all'
=> true
irb(main):002:0> 1.week.ago
=> 2010-11-14 17:56:16 -0700...