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【DM版本】: DM8
【操作系统】：WINDOWS10
【CPU】: intel
【问题描述】*：

• 在达梦中执行select语句速度需要11s左右，但在mysql中执行仅需1.5s左右；
• 表索引已同步至达梦表中
• 表量级在320w左右

具体信息

sql语句

SELECT "area_code" as "area_code", "occur_period_year" as "year", "occur_period_month" as "month", "index_value" as "value", "unit_use" as "unit", "index_code" as "index_code", "dim_cal" as "dim_cal"
FROM "macro_index_data"
WHERE "index_code" = 'gmjj_jjzl_01'
AND "dim_cal" = 'JDZ'
AND "dim_dur" = 'DNLJ'
AND ("dim_extra" = '' or "dim_extra" is null)
AND "occur_period_month" IN(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
AND "area_code" IN('440300000000')
ORDER BY "occur_period_year" desc, "occur_period_month" desc

执行计划

索引信息

请问该如何优化呢？最好是能从数据库方面下手，改动sql语句需要其它同事参与，会耗时较久[苦涩]