Hello
I would like to know how can I define/create a new aggregate function. I
need a custom function that operate on a set of text strings and return a
certain string aggregate based on certain rules. But I cannot figure out how
can I define such a data set to operate on.
any hints?
cl.
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"Claudio Lapidus" <cl******@hotma il.com> writes: Hello
I would like to know how can I define/create a new aggregate function. I need a custom function that operate on a set of text strings and return a certain string aggregate based on certain rules. But I cannot figure out how can I define such a data set to operate on.
Is this example helpful?
create function concat_agg_accu m(varchar, varchar) returns varchar
as 'select $1 || '', '' || $2'
language sql
strict immutable;
create aggregate concat_agg (
basetype = varchar,
stype = varchar,
sfunc = concat_agg_accu m
);
--
greg
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Greg Stark wrote: Is this example helpful?
Yes, perfect! Thank you.
cl. create function concat_agg_accu m(varchar, varchar) returns varchar as 'select $1 || '', '' || $2' language sql strict immutable;
create aggregate concat_agg ( basetype = varchar, stype = varchar, sfunc = concat_agg_accu m );
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just wasted a long time figuring out this and I figure if I post it
might save someone some pain!
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by: BillCo |
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I just wasted a long time figuring out this and I figure if I post it
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