Hola, este truco nos puede ayudar mucho:
--- Truco 1:
SELECT
proname AS functionname,
prosrc AS source
FROM
pg_proc
WHERE
prosrc ~* ‘texto';
http://stackoverflow.com/questions/4448907/search-grep-alike-through-postgresql-functions
--- Truco 2:
select proname,prosrc from pg_proc where prosrc like '%texto%';
http://stackoverflow.com/questions/27257681/search-text-of-all-functions-in-pgadmin
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