SELECT * FROM pg_stat_user_indexes WHERE relname = 'TABLE_NAME':
idx_scan: how many times the index was usedidx_tup_read: how many index entries were returned using the indexidx_tup_fetch: how many rows were returned using the index
You want:
idx_scanto move up (ie, the index is used)idx_tup_read/idx_tup_fetchto move up but not too much (ie, the index is highly selective)