# EXPLAIN SELECT ARRAY_AGG(hashed) FROM words_nouns
WHERE added > to_timestamp(0) UNION SELECT ARRAY_AGG(hashed) FROM words_verbs WHERE added > to_timestamp(0) ; QUERY PLAN ------------------------------------------------------------------------------------------------ Unique (cost=2361.99..2362.00 rows=2 width=32) -> Sort (cost=2361.99..2361.99 rows=2 width=32) Sort Key: (array_agg(words_nouns.hashed)) -> Append (cost=1517.06..2361.98 rows=2 width=32) -> Aggregate (cost=1517.06..1517.07 rows=1 width=32) -> Seq Scan on words_nouns (cost=0.00..1517.05 rows=1 width=32) Filter: (added > '1970-01-01 01:00:00+01'::timestamp with time zone) -> Aggregate (cost=844.88..844.89 rows=1 width=32) -> Seq Scan on words_verbs (cost=0.00..844.88 rows=1 width=32) Filter: (added > '1970-01-01 01:00:00+01'::timestamp with time zone) (10 rows)