Start project idea error:
java.sql.SQLException: Unknown system variable 'query_cache_size'
The reason is that the database driver does not correspond to the database version
terms of settlement:
_ For example, mybatis uses the driver of mysql-5.1.14, and the data source configured by mybatis is connected to mysql-8.0.11. Modify the POM file as follows:
<dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>8.0.11</version> </dependency>
According to the official statement:
The query cache is deprecated as of MySQL 5.7.20, and is removed in MySQL 8.0. Deprecation includes query_cache_size.
It means that query cache has been out of date since MySQL 5.7.20, but it has been removed since MySQL 8.0.
I’ll just change it to 8.0.11.