Re: variable value in array_to_string - Mailing list pgsql-general

DO $$

DECLARE

vresult text;

begin

EXECUTE $qry$

  WITH cols (c) AS ( VALUES ('col1'),('col2') )

  SELECT string_agg('a.' || cols.c, ',')

  FROM cols

  WHERE 'foo' = $1

$qry$

USING 'foo'

INTO vresult;

RAISE NOTICE '%', vresult;

END;

$$;

I still haven't actually figured out what your question is which is maybe why I'm coming across as patronizing.  And while I get that what you wrote is technically correct its using capabilities that have since be superseded by more readable and less error-prone facilities.

The docs do explain this material in terms of technical capabilities.  For better and worse it doesn't always go to great lengths (or keeps up with changing times) to describe best practices or how multiple pieces fit together.