Re: PATCH: psql tab completion for SELECT

On 6 April 2018 at 13:29, Peter Eisentraut
<peter.eisentraut@2ndquadrant.com> wrote:
> The selection of which functions to show can be further refined.
>
> I don't think the contents of pg_amproc and pg_cast should be excluded.
> Some of those functions are useful.  Similarly for pg_operator.oprcode.
>
> Things like oprrest and oprjoin will already be excluded because they
> have "internal" arguments.  Similarly for some columns in pg_aggregate.

You're right.  There were lots of useful functions being excluded by
the pg_amproc, pg_cast, and oprcode checks.  And all the oprrest and
oprjoin functions are already excluded, so I can remove that check.

Perhaps we should remove the "appears in this catalog table" exclusion
checks, and just use argument and return type?

> There are also additional pseudo-types that should be excluded.  See
> pg_type.typtype = 'p', except some of those should not be excluded.
> Needs more thought.

I don't know much about some of the pseudotypes but this is what I propose:

any*, record, _record, cstring should NOT be excluded
void should NOT be excluded for return type (and perhaps in general;
void_out and void_send are callable, if not hugely useful in psql)

trigger, event_trigger should be excluded
internal, opaque, unknown, pg_ddl_command should be excluded
language_handler, tsm_handler, index_am_handler, fdw_handler should be excluded

For modern servers, our query can be simplified to something like:

SELECT distinct pg_catalog.quote_ident(p.proname)
FROM pg_catalog.pg_proc p
WHERE NOT arrayoverlap(ARRAY['internal', 'event_trigger', 'internal',
'opaque', 'unknown', 'pg_ddl_command', 'language_handler',
'tsm_handler', 'index_am_handler', 'fdw_handler']::regtype[]::oid[],
    ARRAY(SELECT p.prorettype UNION SELECT unnest(proargtypes)));

What do you think?