给我优化MySQL语句SELECT o.biz_code AS bizCode, COALESCE ( SUM( d.article_num ),NULL) AS allsendnum, COALESCE ( SUM( CASE WHEN d.article_id IS NOT NULL AND d.article_id = 15 THEN d.article_num ELSE 0 END ),NULL) AS glass1sendnum, COALESCE ( SUM( CASE WHEN d.article_id IS NOT NULL AND d.article_id = 16 THEN d.article_num ELSE 0 END ),NULL) AS glass2sendnum, COALESCE ( SUM( CASE WHEN d.article_id IS NOT NULL AND d.article_id = 63 THEN d.article_num ELSE 0 END ),NULL) AS glass3sendnum FROM tborder o LEFT JOIN tborder_detail d ON o.order_no = d.order_no WHERE o.biz_code IN ('147DEF0026B','146AC0160F6','139A98F73D6','139A98F73D6','146AC0160F6','146AC0160F6') AND o.order_type IN (1,2,3,4,5,6) GROUP BY o.biz_code
时间: 2024-04-12 13:31:00 浏览: 108
关于SQL语句的优化
为了优化这个MySQL查询语句,可以考虑以下几个方面:
1. 索引优化:为`tborder`表的`order_no`列和`biz_code`列创建索引,为`tborder_detail`表的`order_no`列创建索引,以加快查询速度。
2. 去除冗余的WHERE条件:在WHERE子句中,`o.biz_code`列有重复值,可以去除重复的值,只保留唯一的值。
3. 使用JOIN替代LEFT JOIN:根据查询需求,可以将LEFT JOIN改为INNER JOIN,前提是`tborder`表与`tborder_detail`表之间的关联是一对多的关系,这样可以提高查询效率。
4. 避免使用COALESCE函数:在SELECT子句中,使用COALESCE函数对SUM结果进行处理,可以直接在SUM函数中使用IFNULL函数来处理NULL值,避免使用COALESCE函数。
综上所述,优化后的MySQL查询语句如下所示:
```sql
SELECT
o.biz_code AS bizCode,
SUM(IFNULL(d.article_num, 0)) AS allsendnum,
SUM(IF(d.article_id = 15, d.article_num, 0)) AS glass1sendnum,
SUM(IF(d.article_id = 16, d.article_num, 0)) AS glass2sendnum,
SUM(IF(d.article_id = 63, d.article_num, 0)) AS glass3sendnum
FROM
tborder o
INNER JOIN tborder_detail d ON o.order_no = d.order_no
WHERE
o.biz_code IN ('147DEF0026B','146AC0160F6','139A98F73D6')
AND o.order_type IN (1,2,3,4,5,6)
GROUP BY
o.biz_code
```
通过上述优化措施,可以提高查询性能和效率。请注意,具体的优化策略还需要结合数据库的实际情况和数据量进行综合考虑。
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