增加强制索引依然慢

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版本: 阿里云RDS MySQL 8.0.25

线上数据库CPU达到100%, 定位到如下SQL

EXPLAIN 
SELECT ssd.goods_no,ssd.goods_name,ssd.goods_spec,ssd.goods_unit,ssd.create_time,w.warehouse_name,sb.batch_no,swl.warehouse_region_location_name,sc.customer_name AS goodsOwnerName,sc2.customer_name AS supplierName,ss.storage_id,ss.storage_no,ss.storage_desc,sbdl.storage_type,sbdl.create_time AS finishTime,sbdl.before_quantity,sbdl.quantity AS real_quantity,sbdl.after_quantity,sc3.customer_name,sbdl.storage_category,sb.warehouse_owner_goods_id,sb.goods_owner_id
FROM store_batch_details_log sbdl INNER JOIN store_storage_details ssd ON ssd.storage_details_id = sbdl.storage_details_idINNER JOIN store_storage ss  ON ss.storage_id = ssd.storage_idINNER JOIN store_batch_details sbd ON sbd.batch_details_id = sbdl.batch_details_idINNER JOIN store_batch sb ON sb.batch_id = sbd.batch_id LEFT JOIN store_warehouse_location swl ON swl.warehouse_location_id = sbd.warehouse_location_idLEFT JOIN store_customer sc ON sc.customer_id = sb.goods_owner_idLEFT JOIN store_customer sc3 ON sc3.customer_id = ss.customer_idLEFT JOIN warehouse w ON w.warehouse_id = ssd.warehouse_idLEFT JOIN store_customer sc2 ON sc2.customer_id = sb.supplier_id
WHERE 1 = 1AND ssd.`goods_name` LIKE CONCAT('%', '【堂食专供】葡萄（计重）', '%')AND ss.enterprise_id = 241240455403319296AND ss.warehouse_id IN (272697524450807808 , 278854886203117568,358283733083942912,358310610389495808,358316852142993408,358317205127229440,358317497189199872,358319149438791680,358320040363487232,362996967464562688,362998068574220288,372377440368259072,372377840450334720,375321342717001728,377847160517230592,382166980817661952,382167317834182656,383586763626799104,392392204255334400,395668297183764480,395668683634352128,416633733303848960,427869257024753664,432595648538574848,433271921665474560,433660539047346176,434765698913632256,460080655901245440)ORDER BY ss.create_time DESCLIMIT 0,20 ;

执行计划如下

ss表全表扫描

因为在 ss 表上存在索引 idx_enterprise_id_warehouse_id_create_time , 既然没有使用索引, 与查询的条件有关. 于是条件上删除了一些仓库, SQL如下

EXPLAIN 
SELECT ssd.goods_no,ssd.goods_name,ssd.goods_spec,ssd.goods_unit,ssd.create_time,w.warehouse_name,sb.batch_no,swl.warehouse_region_location_name,sc.customer_name AS goodsOwnerName,sc2.customer_name AS supplierName,ss.storage_id,ss.storage_no,ss.storage_desc,sbdl.storage_type,sbdl.create_time AS finishTime,sbdl.before_quantity,sbdl.quantity AS real_quantity,sbdl.after_quantity,sc3.customer_name,sbdl.storage_category,sb.warehouse_owner_goods_id,sb.goods_owner_id
FROM store_batch_details_log sbdl INNER JOINstore_storage_details ssd ON ssd.storage_details_id = sbdl.storage_details_idINNER JOINstore_storage ss  ON ss.storage_id = ssd.storage_idINNER JOIN store_batch_details sbd ON sbd.batch_details_id = sbdl.batch_details_idINNER JOIN store_batch sb ON sb.batch_id = sbd.batch_id LEFT JOIN store_warehouse_location swl ON swl.warehouse_location_id = sbd.warehouse_location_idLEFT JOIN store_customer sc ON sc.customer_id = sb.goods_owner_idLEFT JOIN store_customer sc3 ON sc3.customer_id = ss.customer_idLEFT JOIN warehouse w ON w.warehouse_id = ssd.warehouse_idLEFT JOIN store_customer sc2 ON sc2.customer_id = sb.supplier_id
WHERE 1 = 1AND ssd.`goods_name` LIKE CONCAT('%', '【堂食专供】葡萄（计重）', '%')AND ss.enterprise_id = 241240455403319296AND ss.warehouse_id IN (272697524450807808 , 278854886203117568,358283733083942912,358310610389495808,358316852142993408,358317205127229440,358317497189199872,358319149438791680,358320040363487232,362996967464562688,432595648538574848,433271921665474560,433660539047346176,434765698913632256,460080655901245440)ORDER BY ss.create_time DESCLIMIT 0,20 ;

执行计划如下

ss表使用了索引, row值也变少了 .

于是第一步的优化, 针对第一个原始的SQL, 采用了强制索引

EXPLAIN 
SELECT ssd.goods_no,ssd.goods_name,ssd.goods_spec,ssd.goods_unit,ssd.create_time,w.warehouse_name,sb.batch_no,swl.warehouse_region_location_name,sc.customer_name AS goodsOwnerName,sc2.customer_name AS supplierName,ss.storage_id,ss.storage_no,ss.storage_desc,sbdl.storage_type,sbdl.create_time AS finishTime,sbdl.before_quantity,sbdl.quantity AS real_quantity,sbdl.after_quantity,sc3.customer_name,sbdl.storage_category,sb.warehouse_owner_goods_id,sb.goods_owner_id
FROM store_batch_details_log sbdl INNER JOIN store_storage_details ssd ON ssd.storage_details_id = sbdl.storage_details_idINNER JOIN store_storage ss force index(idx_enterprise_id_warehouse_id_create_time) ON ss.storage_id = ssd.storage_idINNER JOIN store_batch_details sbd ON sbd.batch_details_id = sbdl.batch_details_idINNER JOIN store_batch sb ON sb.batch_id = sbd.batch_id LEFT JOIN store_warehouse_location swl ON swl.warehouse_location_id = sbd.warehouse_location_idLEFT JOIN store_customer sc ON sc.customer_id = sb.goods_owner_idLEFT JOIN store_customer sc3 ON sc3.customer_id = ss.customer_idLEFT JOIN warehouse w ON w.warehouse_id = ssd.warehouse_idLEFT JOIN store_customer sc2 ON sc2.customer_id = sb.supplier_id
WHERE 1 = 1AND ssd.`goods_name` LIKE CONCAT('%', '【堂食专供】葡萄（计重）', '%')AND ss.enterprise_id = 241240455403319296AND ss.warehouse_id IN (272697524450807808 , 278854886203117568,358283733083942912,358310610389495808,358316852142993408,358317205127229440,358317497189199872,358319149438791680,358320040363487232,362996967464562688,362998068574220288,372377440368259072,372377840450334720,375321342717001728,377847160517230592,382166980817661952,382167317834182656,383586763626799104,392392204255334400,395668297183764480,395668683634352128,416633733303848960,427869257024753664,432595648538574848,433271921665474560,433660539047346176,434765698913632256,460080655901245440)ORDER BY ss.create_time DESCLIMIT 0,20 ;

如上, 使用了 force index(idx_enterprise_id_warehouse_id_create_time) . 执行计划如下

ss表终于使用了索引, row值也变少了 . 可在实际执行SQL语句时, 耗时14左右, 依然不理想.

继续使用 SHOW PROFILE查看具体的资源消耗使用情况

待续…

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