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Should I use != or for not equal in T-SQL?
...Server AKA T-SQL. If you're using it in stored procedures there is no performance reason to use one over the other. It then comes down to personal preference. I prefer to use <> as it is ANSI compliant.
You can find links to the various ANSI standards at...
http://en.wikipedia.org/wiki/SQL
...
What is Rack middleware?
...uthentication, name/password?
Authorisation: "is the user authorised to perform this particular task?", i.e. role-based security.
Caching: have I processed this request already, can I return a cached result?
Decoration: how can I enhance the request to make downstream processing better?
Performance ...
PHP $_SERVER['HTTP_HOST'] vs. $_SERVER['SERVER_NAME'], am I understanding the man pages correctly?
...o, array_key_exists is more scalable compared to in_array that has O(n) performance.
– Pacerier
Mar 5 '15 at 23:43
2
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In Matplotlib, what does the argument mean in fig.add_subplot(111)?
...grid, first subplot" and "234" means "2x3 grid, 4th subplot".
Alternative form for add_subplot(111) is add_subplot(1, 1, 1).
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What is the proper declaration of main?
...e that all of this applies only when compiling for a hosted environment (informally, an environment where you have a full standard library and there's an OS running your program). It is also possible to compile a C++ program for a freestanding environment (for example, some types of embedded system...
Sending Arguments To Background Worker?
...orker1_DoWork(object sender, DoWorkEventArgs e)
{
// Do not access the form's BackgroundWorker reference directly.
// Instead, use the reference provided by the sender parameter.
BackgroundWorker bw = sender as BackgroundWorker;
// Extract the argument.
int arg = (int)e.Argument...
In Django, how does one filter a QuerySet with dynamic field lookups?
...nt expansion may be used to solve this problem:
kwargs = {
'{0}__{1}'.format('name', 'startswith'): 'A',
'{0}__{1}'.format('name', 'endswith'): 'Z'
}
Person.objects.filter(**kwargs)
This is a very common and useful Python idiom.
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How to check file MIME type with javascript before upload?
...that the real validation still has to be done on server side. I want to perform a client side checking to avoid unnecessary wastage of server resource.
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Mongodb Explain for Aggregation framework
...ns
As at MongoDB 3.4, the Aggregation Framework explain option provides information on how a pipeline is processed but does not support the same level of detail as the executionStats mode for a find() query. If you are focused on optimizing initial query execution you will likely find it beneficial...
Shell equality operators (=, ==, -eq)
...riting a #!/bin/bash script then I recommend using [[ instead. The doubled form has more features, more natural syntax, and fewer gotchas that will trip you up. Double quotes are no longer required around $a, for one:
$ [[ $a == foo ]]; echo "$?" # bash specific
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See also:
What's the diff...