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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...
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&...
How can I group by date time column without taking time into consideration
I have a bunch of product orders and I'm trying to group by the date and sum the quantity for that date. How can I group by the month/day/year without taking the time part into consideration?
...
SQL Server add auto increment primary key to existing table
... I would like to start counting at 1000. I suspect I can use ALTER TABLE ORDER ALTER COLUMN ORDERNO RESTART WITH 1 but I didn't want to try it without checking with an expert :) Ref. pic.dhe.ibm.com/infocenter/iseries/v7r1m0/…
– user1477388
Mar 8 '13 at 1...
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...
...
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...
How to normalize an array in NumPy?
...iving optimal performance.
import numpy as np
def normalized(a, axis=-1, order=2):
l2 = np.atleast_1d(np.linalg.norm(a, order, axis))
l2[l2==0] = 1
return a / np.expand_dims(l2, axis)
A = np.random.randn(3,3,3)
print(normalized(A,0))
print(normalized(A,1))
print(normalized(A,2))
prin...
PHP - Check if two arrays are equal
...$a === $b); // TRUE if $a and $b have the same key/value pairs in the same order and of the same types.
See Array Operators.
EDIT
The inequality operator is != while the non-identity operator is !== to match the equality
operator == and the identity operator ===.
...
How to get primary key column in Oracle?
...ND cons.constraint_name = cols.constraint_name
AND cons.owner = cols.owner
ORDER BY cols.table_name, cols.position;
Make sure that 'TABLE_NAME' is in upper case since Oracle stores table names in upper case.
share
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How do I delete a Git branch locally and remotely?
...should run git remote prune <name> (e.g. git remote prune origin) in order to locally remove stale branches that no longer exist in the remote.
– code_dredd
Apr 18 '16 at 23:07
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