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Rails: Default sort order for a rails model?
...ow use Book.published.confirmed.
With this method, the query is not actually executed until actual results are needed (lazy evaluation), so 7 scopes could be chained together but only resulting in 1 actual database query, to avoid performance problems from executing 7 separate queries.
You can u...
ab load testing
...While ab runs, there will be -c clients hitting the site. This is what actually decides the amount of stress your site will suffer during the benchmark.
-n: Indicates how many requests are going to be made. This just decides the length of the benchmark. A high -n value with a -c value that your ser...
Automatic prune with Git fetch or pull
... work is over and I don't know, I won't do a git fetch --prune and eventually I will push back the deleted branch.
3 Answ...
Possible to change where Android Virtual Devices are saved?
... \.android" by default. Is there any way to change this behavior? I have all of the other components saved in a directory on a separate partition and would like everything to be consolidated. Obviously not a huge deal but does anyone here know a workaround for this?
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Is it better in C++ to pass by value or pass by constant reference?
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It used to be generally recommended best practice1 to use pass by const ref for all types, except for builtin types (char, int, double, etc.), for iterators and for function objects (lambdas, classes deriving from std::*_function).
This was es...
Best way to test if a row exists in a MySQL table
...RE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything at all. MySQL
ignores the SELECT list in such a subquery, so it makes no difference.
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How can I start PostgreSQL server on Mac OS X?
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The Homebrew package manager includes launchctl plists to start automatically. For more information, run brew info postgres.
Start manually
pg_ctl -D /usr/local/var/postgres start
Stop manually
pg_ctl -D /usr/local/var/postgres stop
Start automatically
"To have launchd start postgresql now and res...
Mapping over values in a python dictionary
..., f(kv[1])), my_dictionary.iteritems()))
but that's not that readable, really.
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Use Font Awesome Icon in Placeholder
...possible to use Font Awesome Icon in a Placeholder? I read that HTML isn't allowed in a placeholder. Is there a workaround?
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Any way to select without causing locking in MySQL?
...ere are locks and opposing to InnoDB those locks are table locks, blocking all requested WRITE locks and all subsequent queries during execution. The original question appears to be about InnoDB though and isolation levels are non-existent for MyISAM too - the docs for the SET TRANSACTION statement ...