Re: Function array_agg(array) - Mailing list pgsql-hackers

From Ali Akbar
Subject Re: Function array_agg(array)
Date
Msg-id CACQjQLpz3CymUFi66ccB5JzPUTKnzZkhDBB=_cgUVSUSKjdhcQ@mail.gmail.com
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In response to Re: Function array_agg(array)  (Pavel Stehule <pavel.stehule@gmail.com>)
Responses Re: Function array_agg(array)
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I fixed small issue in regress tests and I enhanced tests for varlena types and null values.
Thanks.

it is about 15% faster than original implementation.
15% faster than array_agg(scalar)? I haven't verify the performance, but because the internal array data and null bitmap is copied as-is, that will be faster.

2014-10-25 1:51 GMT+07:00 Pavel Stehule <pavel.stehule@gmail.com>:
Hi Ali 

I checked a code. I am thinking so code organization is not good. accumArrayResult is too long now. makeMdArrayResult will not work, when arrays was joined (it is not consistent now). I don't like a usage of state->is_array_accum in array_userfunc.c -- it is signal of wrong wrapping.
Yes, i was thinking the same. Attached WIP patch to reorganizate the code. makeMdArrayResult works now, with supplied arguments act as override from default values calculated from ArrayBuildStateArray.

In array_userfunc.c, because we don't want to override ndims, dims and lbs, i copied array_agg_finalfn and only change the call to makeMdArrayResult (we don't uses makeArrayResult because we want to set release to false). Another alternative is to create new makeArrayResult-like function that has parameter bool release.
 
next question: there is function array_append(anyarray, anyelement). Isn't time to define array_append(anyarray, anyarray) now? 

There is array_cat(anyarray, anyarray):
/*-----------------------------------------------------------------------------
 * array_cat :
 * concatenate two nD arrays to form an nD array, or
 * push an (n-1)D array onto the end of an nD array
 *----------------------------------------------------------------------------
 */

Regards,
--
Ali Akbar
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