Confused by result of pg_catalog.format_type()

Here's an example:

pagila=# select pg_catalog.format_type(prorettype, NULL) from pg_proc
where proname='foo_ins_trig';

format_type
-------------
"trigger"
(1 row)

Time: 3.212 ms
pagila=# SELECT 1
FROM pg_proc p
WHERE p.proname='foo_ins_trig'
AND pg_catalog.format_type(p.prorettype, NULL) = 'trigger';

?column?
----------
(0 rows)

Time: 0.736 ms
pagila=#

What am I missing?

Erik Jones

DBA | Emma®
erik(at)myemma(dot)com
800.595.4401 or 615.292.5888
615.292.0777 (fax)

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