Re: How do I create an array?
От
Tom Lane
Тема
Re: How do I create an array?
Дата
Msg-id
12000.1044541596@sss.pgh.pa.us
Ответ на
Re: How do I create an array? (Joe Conway)
Список
Дерево обсуждения
How do I create an array? Greg Stark <gsstark@mit.edu>
Re: How do I create an array? Tom Lane <tgl@sss.pgh.pa.us>
Re: How do I create an array? Joe Conway <mail@joeconway.com>
Re: How do I create an array? Tom Lane <tgl@sss.pgh.pa.us>
Re: How do I create an array? Joe Conway <mail@joeconway.com>
Re: How do I create an array? Tom Lane <tgl@sss.pgh.pa.us>
Joe Conway writes: > Actually, while I was at it I also wrote a C function called "array" which can > be declared to take as many arguments (to the max allowed) and return a > corresponding array. It is useful since R likes to work with arrays. E.g: > CREATE OR REPLACE FUNCTION array (float8, float8) RETURNS float8[] AS > '$libdir/plr','array' LANGUAGE 'C' WITH (isstrict); Yeah, that's what I was referring to by a "bespoke function". You'd need one for every datatype; plus an entry in pg_proc for every number of arguments you want to support (and it won't scale past MAX_FUNC_ARGS). Doesn't seem like the avenue to a general solution. This morning I was musing about overloading the CAST syntax to allow array construction, along the lines of CAST((x,y,z+2) AS float8[]) Perhaps multidimensional arrays could be done like this CAST(((a11,a12,a13), (a21,a22,a23)) AS float8[]) But there are other ways you could imagine doing it, too. regards, tom lane
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