After using mybatis for so long, let's see how it works today.
When configuring spring mybatis, we will have a spring-mybatis.xml file. which defines such a bean
fly.fky.restapi.dao //这是一个包名, dao 的声明都在这里When we start the service, the MapperScannerConfigurer class will parse the package we configured
Register in the global beanFactory
This configures some of our sql statement file paths
After these files are parsed, <insert>, <delete>, <update>, <select> will be parsed into MappedStatement objects.
A MappedStatement corresponds to an <insert>, <delete>, <update>, <select> in the mapper file, and the corresponding MappedStatement is obtained each time a MyBatis operation is performed.
Call selectOne through the SqlSessionTemplate class proxy
Then enter DefaultSqlSession to find the MappedStatement parsed and stored above
This is where the sql statement is actually executed.