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IN vs OR in the SQL WHERE Clause
...rding to the manual for MySQL if the values are constant IN sorts the list and then uses a binary search. I would imagine that OR evaluates them one by one in no particular order. So IN is faster in some circumstances.
The best way to know is to profile both on your database with your specific dat...
Add unique constraint to combination of two columns
I have a table and, somehow, the same person got into my Person table twice. Right now, the primary key is just an autonumber but there are two other fields that exist that I want to force to be unique.
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Set default syntax to different filetype in Sublime Text 2
...the menu bar. Open a file with the extension you want to set a default for and navigate through the following menus: View -> Syntax -> Open all with current extension as... ->[your syntax choice].
Updated 2012-06-28: Recent builds of Sublime Text 2 (at least since Build 2181) have allowed ...
Include intermediary (through model) in responses in Django Rest Framework
I have a question about dealing with m2m / through models and their presentation in django rest framework. Let's take a classic example:
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What is the difference between ui-bootstrap-tpls.min.js and ui-bootstrap.min.js?
...n. You would want to use the non tpls version if you have a custom way to handle/deliver all your partials and did not want them included in the main library.
– cyberwombat
Feb 2 '15 at 22:19
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Check for array not empty: any?
...something or not. This includes things that evaluate to false, such as nil and false.
>> a = []
=> []
>> a.empty?
=> true
>> a = [nil, false]
=> [nil, false]
>> a.empty?
=> false
>> a = [nil]
=> [nil]
>> a.empty?
=> false
The method any? comes ...
GCD to perform task in main thread
...are on the main thread, the behaviour is the same: the block is scheduled, and executed when the run loop of the main thread is run.
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How does a garbage collector avoid an infinite loop here?
...kes dramatically under 40 seconds per object. That a new object is created and then eligible for finalization is not relevant to the current finalizer.
– Jacob Krall
Jul 10 '14 at 16:09
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What are the differences between .gitignore and .gitkeep?
What are the differences between .gitignore and .gitkeep ? Are they the same thing with a different name, or do they both serve a different function?
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What is a Proxy in Doctrine 2?
... just finished reading all the Doctrine 2 documentation, I started my own sandbox, I understood most of the principes, but there is still a question and I couldn't find any complete explanation in the doc.
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