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Overriding a Rails default_scope
... you end up putting this in a class method like: def self.random; unscoped.order('rand()'); end unscoped removes ALL sql before it, not just what is listed under default_scope. While technically a correct answer, be careful using unstopped
– Schneems
Dec 25 '11...
Creating a daemon in Linux
...daemon process, change the current directory to the root directory (/), in order to avoid that the daemon involuntarily blocks mount points from being unmounted.
In the daemon process, write the daemon PID (as returned by getpid()) to a PID file, for example /run/foobar.pid (for a hypothetical dae...
How do you convert a time.struct_time object into a datetime object?
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Multiple select statements in Single query
I am generating a report in php (mysql),
6 Answers
6
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Wait until all jQuery Ajax requests are done?
...d a ajax request to the queue like this:
$.ajaxQueue({
url: 'page.php',
data: {id: 1},
type: 'POST',
success: function(data) {
$('#status').html(data);
}
});
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What are the differences between a clustered and a non-clustered index?
...le
Faster to read than non clustered as data is physically stored in index order
Non Clustered Index
Can be used many times per table
Quicker for insert and update operations than a clustered index
Both types of index will improve performance when select data with fields that use the index but...
Random record in ActiveRecord
...d = Model.first(:offset => offset)
To be honest, I've just been using ORDER BY RAND() or RANDOM() (depending on the database). It's not a performance issue if you don't have a performance issue.
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WebSocket with SSL
... request where the WS server is running. e.g: ws://10.12.23.45:5641/server.php. and I know its a very bad solution - although, it works for me. I'd appreciate your help if you guide me through the apache configuration. e.g: where to put the .cert etc. thanks!
– muaaz
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Escaping a forward slash in a regular expression
...it by putting a backward slash in front of it: \/ For some languages (like PHP) you can use other characters as the delimiter and therefore you don't need to escape it. But AFAIK in all languages, the only special significance the / has is it may be the designated pattern delimiter.
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gcc warning" 'will be initialized after'
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Make sure the members appear in the initializer list in the same order as they appear in the class
Class C {
int a;
int b;
C():b(1),a(2){} //warning, should be C():a(2),b(1)
}
or you can turn -Wno-reorder
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