How to improve the performance of SQL
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1 the initial sql implementation is as follows
SQL > SELECT 2 NVL (T.RELA_OFFER_SPEC_ID SUBOS.SUB_OFFER_SPEC_ID) "offerSpecId" 3 FROM OFFER_SPEC_RELA T 4 LEFT JOIN OFFER_SPEC_GRP_RELA SUBOS 5 ON T.RELA_GRP_ID = SUBOS.OFFER_SPEC_GRP_ID 6 AND subos.start_dt = SYSDATE 8 WHERE T.RELA_TYPE_CD = 29 AND t.start_dt = SYSDATE 11 AND (T.OFFER_SPEC_ID = 109910000618 12 OR EXISTS 13 (SELECT A.OFFER_SPEC) _ GRP_ID 14 FROM OFFER_SPEC_GRP_RELA A 15 WHERE A.SUB_OFFER_SPEC_ID = 109910000618 16 AND T.OFFER_SPEC_GRP_ID = A.OFFER_SPEC_GRP_ID 17) 18 AND rownum
