SQL data query optimization select & nbsp;. id, rkno,. packageno & nbsp; as & nbsp; packageno, cust_no, lotno, count (*) & nbsp; as & nbsp; count & nbsp; from & nbsp; 'rk _ record '& SQL data query optimization
Select. id, rkno,. packageno as packageno, cust_no, lotno, count (*) as count from 'rk _ record 'as a right join 'sys _ barcode_1d_y' as B on. packageno = B. packageno where rkno = '000000' group by packageno, lotno order by packageno, lotno asc
Rkno and packageno contain indexes.
The current query requires more than 4000 ms. Is there any way to optimize this SQL statement?
------ Solution --------------------
Table B has no index used
Try to set a. packageno = B. packageno
Writing B. packageno = a. packageno
------ Solution --------------------
No index is used for table B fields. check whether the index is created for the joined fields in Table B.
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
info-contact@alibabacloud.com
and provide relevant evidence. A staff member will contact you within 5 working days.