Performance of complex query is totally depends on the query planner, which depends on 1) table size, 2) data cardinality, 3) table statistics It is only testa

Performance of complex query is totally depends on the query planner, which depends on 1) table size, 2) data cardinality, 3) table statistics It is only testable on real production database, so you can do test of complex queries on backup of your prod to get a sense of performance. But still query can degrade unexpectedly under consistent load in prod from other queries