the code provided is just a little poc to get the error ( which i have not
included with my first mail sorry. )
ERROR: syntax error at or near "DISTINCT"
LINE 8: _test := DISTINCT a FROM ( VALUES ( (true), ( true ) ) )...
the code in production looked like this:
_resource_id :=
DISTINCT ti_resource_id
FROM tabk.resource_timeline
WHERE ti_a2_id = _ab2_id
AND ti_type = 'task'
;
this is backed up by a trigger function, that will ensure to every instance
with the same ti_a2_id exists only one ti_resource_id, hence the query can
never fail due to more than one row beeing returned. but this syntax is not
supported anymore, which will break BC. up until PG 13, the assignment
statement was just an implizit SELECT <expression> Query.
Since Tom Lane didn't mentioned this change in the other thread, i figured the
devteam might not be aware of this chance.
i can refactor this line into
_resource_id :=
ti_resource_id
FROM tabk.resource_timeline
WHERE ti_a2_id = _ab2_id
AND ti_type = 'task'
GROUP BY ti_resource_id
;
but concerns about BC was already raised, although with UNION there might be
far less people affected.
with kind regards, richard
