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How to return result of a SELECT inside a function in PostgreSQL?
...pe = 'ALPHABETIC'
LIMIT _max_tokens
) t
GROUP BY t.txt
ORDER BY cnt DESC; -- potential ambiguity
END
$func$ LANGUAGE plpgsql;
Call:
SELECT * FROM word_frequency(123);
Explanation:
It is much more practical to explicitly define the return type than sim...
How to force R to use a specified factor level as reference in a regression?
...level() command is a shorthand method to your question. What it does is reorder the factor so that whatever is the ref level is first. Therefore, reordering your factor levels will also have the same effect but gives you more control. Perhaps you wanted to have levels 3,4,0,1,2. In that case...
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Ways to iterate over a list in Java
...dingly. There's no "copying" per-se, but because of the language design in order to make changes to the contents of e I'd have to call one of e's methods because assignment just changes the pointer (pardon my C).
– jacobq
Aug 23 '13 at 20:03
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What is the difference between an IntentService and a Service? [duplicate]
...d on your system. For example,
If you went to a hotel and you give your order for a soup to a server
The server gets your order and sends to chef
You don't know how the soup is made in the kitchen and what processes are required for making the soup
Once your order is ready, the server brings you ...
Views vs Components in Ember.js
...able Components when a route is entered, instead of a controller/view. In order to future proof your app, it's best to stay away from Views.
Sources:
Road to Ember 2.0: https://github.com/emberjs/rfcs/pull/15
Future-proofing your Ember 1.x code: https://gist.github.com/samselikoff/1d7300ce59d21...
psql: FATAL: Ident authentication failed for user “postgres”
...
Edit the file /etc/postgresql/8.4/main/pg_hba.conf and replace ident or peer by either md5 or trust, depending on whether you want it to ask for a password on your own computer or not.
Then reload the configuration file with:
/etc/init.d/p...
What is the difference between :focus and :active?
...
Nit: the order of focus and active affects the state of a HTML button if there is no :active:focus state - Putting :active state after :focus, I get the active changes when I hit tab and hit space. If :focus is last, I never see the a...
Get difference between two lists
... and point out that this only returns the temp1-temp2? .. As other said in order to return all the differences you have to use the sysmetric difference: list(set(temp1) ^ set(temp2))
– rkachach
Feb 16 '16 at 16:00
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Is there a way to instantiate objects from a string holding their class name?
...ram termination)
// because we can't guarantee correct destruction order
if(!map) { map = new map_type; }
return map;
}
private:
static map_type * map;
};
template<typename T>
struct DerivedRegister : BaseFactory {
DerivedRegister(std::string const&...
When to throw an exception?
...es not expect. UserNameNotValidException , PasswordNotCorrectException etc.
32 Answers
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