Review: listagg aggregate
in [PgSql]
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From: Robert Haas on 25 Jan 2010 15:14 On Mon, Jan 25, 2010 at 2:27 PM, David E. Wheeler <david(a)kineticode.com> wrote: > On Jan 25, 2010, at 2:09 AM, Peter Eisentraut wrote: >> xmlagg -> concatenates values to form xml datum >> array_agg -> concatenates values to form array datum >> ??? -> concatenates values to form string datum > > concat_agg(). I like that one... ....Robert -- Sent via pgsql-hackers mailing list (pgsql-hackers(a)postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
From: Pavel Stehule on 26 Jan 2010 01:59 2010/1/25 David E. Wheeler <david(a)kineticode.com>: > On Jan 25, 2010, at 6:12 AM, Pavel Stehule wrote: > >> I am not happy, I thing so we do bigger chaos then it is. But it >> hasn't progress. So I agree with name string_agg. In this case isn't a >> problem rename this function if somebody would. > > Could you not use CREATE AGGREGATE to create an alias named listagg if you needed it? Or are we limited to a single argument in that case? we can, but without one common known name we will have a propriety name. Pavel > > David > > > > -- Sent via pgsql-hackers mailing list (pgsql-hackers(a)postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
From: Pavel Stehule on 26 Jan 2010 02:14 2010/1/25 Robert Haas <robertmhaas(a)gmail.com>: > On Mon, Jan 25, 2010 at 2:27 PM, David E. Wheeler <david(a)kineticode.com> wrote: >> On Jan 25, 2010, at 2:09 AM, Peter Eisentraut wrote: >>> xmlagg -> concatenates values to form xml datum >>> array_agg -> concatenates values to form array datum >>> ??? -> concatenates values to form string datum >> >> concat_agg(). > > I like that one... > why is concat_agg better than listagg ? Pavel > ...Robert > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers(a)postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers > -- Sent via pgsql-hackers mailing list (pgsql-hackers(a)postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
From: "David E. Wheeler" on 26 Jan 2010 06:08 On Jan 25, 2010, at 23:14, Pavel Stehule <pavel.stehule(a)gmail.com> wrote: > why is concat_agg better than listagg ? Because it's an aggregate that cocatenates values. It's not an aggregate that lists things. I also like concat_agg better than string_agg because it's not limited to acting on strings. Best, David -- Sent via pgsql-hackers mailing list (pgsql-hackers(a)postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
From: Alastair Turner on 26 Jan 2010 06:23
On Tue, Jan 26, 2010 at 1:08 PM, David E. Wheeler <david(a)kineticode.com> wrote: ...... > > Because it's an aggregate that cocatenates values. It's not an aggregate > that lists things. I also like concat_agg better than string_agg because > it's not limited to acting on strings. > ...... Given that it potentially produces a delimited list, not a straight conacatenation (and that list is unacceptable since it would be descriptive as a noun but not as a verb) would implode_agg not be the most descriptive name? -- Sent via pgsql-hackers mailing list (pgsql-hackers(a)postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers |