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What's wrong with nullable columns in composite primary keys?
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In order for a foreign key to work the refered must be unique (ie. all values must be distinct). Which means that it could have a single null value. All the null values could then refer to that single null if the REFERENCES woul...
How disable Copy, Cut, Select, Select All in UITextView
... method using a category. This is undefined behavior. You must subclass in order to safely override a method.
– Rob Napier
Apr 22 '13 at 18:42
2
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SET versus SELECT when assigning variables?
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+1 It is better to run once in order to understand, check, play, memorize that to just read but other answers are just text
– Gennady Vanin Геннадий Ванин
Oct 16 '10 at 7:36
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Find object by id in an array of JavaScript objects
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As long as you don't rely on the order of properties: stackoverflow.com/questions/4886314/…
– Marle1
Nov 5 '14 at 16:28
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How to get last N records with activerecord?
...method:
Record.last(N)
Example:
User.last(5)
Returns 5 users in descending order by their id.
Deprecated (Old Answer)
An active record query like this I think would get you what you want ('Something' is the model name):
Something.find(:all, :order => "id desc", :limit => 5).reverse
edit: As n...
How to sort a dataframe by multiple column(s)
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You can use the order() function directly without resorting to add-on tools -- see this simpler answer which uses a trick right from the top of the example(order) code:
R> dd[with(dd, order(-z, b)), ]
b x y z
4 Low C 9 2
2 Med D 3 1
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Stateless vs Stateful - I could use some concrete information
...y relevant articles in that area.
Another area that you could research in order to gain more understanding is RESTful web services. These are by design "stateless", in contrast to other web technologies that try to somehow keep state. (In fact what you say that ASP.NET is stateless isn't correct - ...
Position of least significant bit that is set
... i++) {
unsigned int value = nums[i];
// note that order to check indices will depend whether you are on a big
// or little endian machine. This is for little-endian
unsigned char *bytes = (unsigned char *)&value;
if (bytes[0])
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Greedy vs. Reluctant vs. Possessive Quantifiers
... another character, etc. So a greedy quantifier checks possible matches in order from longest to shortest.
A reluctant quantifier tells the engine to start with the shortest possible piece of the string. If it matches, the engine can continue; if not, it adds one character to the section of the stri...
When would you use the different git merge strategies?
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