SQL optimization case: implicit conversion

MySQL is one of the most popular relational databases at present. With the rapid development of the Internet, MySQL database is widely used in the production systems of e-commerce, finance and many other industries. In the actual development, operation and maintenance process, we must often encounter the problem of slow SQL. A SQL with poor per ...

Posted by volant on Tue, 10 May 2022 09:16:01 +0300

SQL optimization case: OR condition optimization

Following is an introduction to the previous article, SQL Optimization Case (1): Implicit Conversion, which focuses on OR optimization. In MySQL, the same query condition, if the OR s are transformed in the SQL statement, the results of the query will be different. In many complex cases, poor index selection may be a potential performance hazar ...

Posted by dewbie on Mon, 09 May 2022 19:28:01 +0300