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How do I get the MIN() of two fields in Postgres?
...ATEST and LEAST are not in the SQL standard, but are a common extension. Some other databases make them return NULL if any argument is NULL, rather than only when all are NULL...
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When should I release objects in -(void)viewDidUnload rather than in -dealloc?
...logic behind -viewDidUnload.
One of the most important reasons for implementing it is that UIViewController subclasses commonly also contain owning references to various subviews in the view hierarchy. These properties could have been set through IBOutlets when loading from a nib, or programmati...
JavaScript OR (||) variable assignment explanation
...ee short-circuit evaluation for the explanation. It's a common way of implementing these operators; it is not unique to JavaScript.
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Advantages of Binary Search Trees over Hash Tables
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Remember that Binary Search Trees (reference-based) are memory-efficient. They do not reserve more memory than they need to.
For instance, if a hash function has a range R(h) = 0...100, then you need to allocate an array of 10...
Real-world applications of zygohistomorphic prepromorphisms
... Mu have a Functional Pearl using zygomorphisms to find maximally dense segments (a generalization of maximum segment sums). Zygomorphisms are seemingly a good fit for sliding window problems once you are accustomed to them.
http://www.iis.sinica.edu.tw/~scm/2010/functional-pearl-maximally-dense-se...
Colspan/Rowspan for elements whose display is set to table-cell
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How to pull a random record using Django's ORM?
...nts paintings I present on my site. On the main webpage I'd like to show some of them: newest, one that was not visited for most time, most popular one and a random one.
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Input with display:block is not a block, why not?
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Check out what I came up with, a solution using the relatively unknown box-sizing:border-box style from CSS 3. This allows a 'true' 100% width on any element regardless of that elements' padding and/or borders.
<!DOCTYPE html PUBLIC "-//W3...
Validating IPv4 addresses with regexp
...o get an efficient regex for IPv4 validation, but without much luck. It seemed at one point I had had it with (25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?(\.|$)){4} , but it produces some strange results:
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Search and replace a line in a file in Python
... to loop over the contents of a text file and do a search and replace on some lines and write the result back to the file. I could first load the whole file in memory and then write it back, but that probably is not the best way to do it.
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