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8-1-1. NL 조인의 비효율

-- [SQL-8-1-a] SELECT 'DROP INDEX startdbpg.' || t1.indexname || ';' script FROM pg_indexes t1 WHERE t1.tablename IN ('tr_ord_big','ms_mbr_big','cm_base_cd','ms_shop_big') AND t1.indexname != t1.tablename || '_pk' AND t1.indexname NOT LIKE t1.tablename || '_fk%' ORDER BY t1.indexname;
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-- [SQL-8-1-1-a] EXPLAIN (ANALYZE,COSTS OFF) SELECT /*+ Leading((t1 t2)) NestLoop(t1 t2) */ t1.mbr_id ,t1.nick_nm ,t2.ord_dtm ,t2.ord_amt FROM startdbpg.ms_mbr_big t1 INNER JOIN startdbpg.tr_ord_big t2 ON (t2.mbr_id = t1.mbr_id) WHERE t1.mbr_gd = 'PLAT' AND t1.join_tp = 'INV' AND t2.ord_dtm >= '2023-12-21'::date AND t2.ord_dtm < '2023-12-26'::date;
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