Re: Weird "could not determine which collation to use for stringcomparison" with LEAST/GREATEST on PG11 procedure - Mailing list pgsql-bugs

On 21/11/2018 19:19, Tom Lane wrote:
> "Voillequin, Jean-Marc" <Jean-Marc.Voillequin@moodys.com> writes:
>> SIMPLE=> create or replace procedure same_values_proc(a text, b text) as $body$
>> SIMPLE$> begin
>> SIMPLE$>        assert a = b;
>> SIMPLE$> end;$body$ language plpgsql;
>> CREATE PROCEDURE
>> SIMPLE=>
>> SIMPLE=> call same_values_proc(least('a','b'),'a');
>> ERROR:  could not determine which collation to use for string comparison
>> HINT:  Use the COLLATE clause to set the collation explicitly.
> 
> Yeah, same here.  I think somebody forgot to run assign_expr_collations()
> on CALL arguments.

This appears to fix it.

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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