Re: PSQL commands: \quit_if, \quit_unless

>> Yes, that is a possibility, but this can already be queried into a
>> :-variable, so it is less indispensable.
>
> can you show some examples, please?

SELECT COUNT(*) AS has_unit_extension
FROM pg_extension WHERE extname='unit' \gset
\echo :has_unit_extension
1

So that

\if ! :hash_unit_extension
CREATE TABLE foo(id SERIAL, stuff UNIT);
\else
\echo "unit extension is not loaded"
\quit
\fi

Ok, for this example one may try:

CREATE EXTENSION IF NOT EXISTS unit;

Or use the "ON_ERROR_STOP" setting, but that is the idea, SQL can be used
to test anything server-side.

--
Fabien.