Postgres 12

By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.
SELECT           now()
UNION ALL SELECT transaction_timestamp()
UNION ALL SELECT current_timestamp;

now

2026-04-16 20:02:45.608725+01

2026-04-16 20:02:45.608725+01

2026-04-16 20:02:45.608725+01

SELECT 3

SELECT           timestamptz 'now'
UNION ALL SELECT timestamptz 'now '
UNION ALL SELECT timestamptz 'now()'
UNION ALL SELECT timestamptz 'now[]'
UNION ALL SELECT timestamptz 'now{}'
UNION ALL SELECT timestamptz 'now}{])))}}{{[[(()'
UNION ALL SELECT timestamptz 'now }{       ]) ) )} } {{[    [(()'
UNION ALL SELECT timestamptz ' }]) now {[( ';

timestamptz

2026-04-16 20:02:45.609691+01

2026-04-16 20:02:45.609691+01

2026-04-16 20:02:45.609691+01

2026-04-16 20:02:45.609691+01

2026-04-16 20:02:45.609691+01

2026-04-16 20:02:45.609691+01

2026-04-16 20:02:45.609691+01

2026-04-16 20:02:45.609691+01

SELECT 8

-- but:
SELECT timestamptz 'now1';

ERROR:  invalid input syntax for type timestamp with time zone: "now1"
LINE 2: SELECT timestamptz 'now1';
                           ^