随笔分类 - sql优化-达梦
index join SLCT 条件过滤性好,怎么将它下推?
摘要:sql select --/*+ enable_index_filter(1) enable_hash_join(0) use_nl_with_index(authallrea2_,IDX_DM_20236274)*/ --/*+ no_semi_gen_cross HI_RIGHT_ORDER_F
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含子查询sql优化案例一例
摘要:0. 排查sql select EXECSQLEXECTIMERANGE,count(*) from SQLLOG_OA_2024 group by EXECSQLEXECTIMERANGE select execsqlstr,paramsstr,count(*) from ( select to_
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分区键有表达式计算引起分区表全表扫描案例
摘要:sql select t.c_port_code c_port_code, sum(abs(t.N_jzbdl)) / nvl( ( select count(1) from T_M_T_FUNDNAV t join ( select p.c_port_code, case when r.c_rel
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view_filter_merging=1 和2 有什么不同?
摘要:sql SELECT count(0) FROM ( SELECT --/*+ view_filter_merging(137)*/ b.C_FIELD1 ZCDM , b.GP3ZZHDM ZZHDM, b.C_FIELD5 KJFL , b.N_FIELD2 QZJG , b.D_FIELD1
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left join 右孩子join条件无法下放
摘要:sql SELECT port.C_PORT_CODE , port.jjmc , port.c_rela_content, A.D_SELL , ( select ta.d_hday from ( select TRUNC(to_date('2024-04-03', 'yyyy-MM-dd'),
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索引定位使用案例-类型转换
摘要:sql select count(0) from (select distinct cc.*, to_char(a1.D_DEALDATE, 'yyyy-MM-dd') D_DEALDATE, a1.C_DATA_IDF, trim(a1.C_FIELD7) ZQFL, trim(a1.C_FIEL
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