Re: proposal: FOREACH-IN-ARRAY (probably for 9.2?)
Merlin Moncure <mmoncure@gmail.com>
From: Merlin Moncure <mmoncure@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Pavel Stehule <pavel.stehule@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Robert Haas <robertmhaas@gmail.com>
Date: 2010-12-17T15:53:42Z
Lists: pgsql-hackers
On Fri, Dec 17, 2010 at 10:47 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote: > Pavel Stehule <pavel.stehule@gmail.com> writes: >> I am resending a redesigned proposal about special plpgsql statement >> that support iteration over an array. > > OK ... > >> == Iteration over multidimensional arrays == >> Its designed to reduce one dimension from source array. It can remove >> a slicing and simplify code: > > This seems like a really bad, confusing idea. I think it should throw > a type-mismatch error in this case. If there is any use-case for such a > thing, which I'm quite unconvinced of, it ought to use a separate syntax > rather than overloading the element-by-element syntax. I don't agree at all -- iterating arrays by slice is a frequently requested feature (you can kinda sorta do it by slice notation, but arr[n] giving null is a -general FAQ. This is how people think arrays should work. I suppose that having this functionality reserved in a tiny corner of plpgsql is not so good, but I think foreach... would become the preferred way to iterate arrays always. merlin