首先，在log4j.properties中添加

log4j.rootLogger=DEBUG,Console,RollingFile

log4j.logger.com.ibatis=DEBUG
log4j.logger.com.ibatis.common.jdbc.SimpleDataSource=DEBUG
log4j.logger.com.ibatis.common.jdbc.ScriptRunner=DEBUG
log4j.logger.com.ibatis.sqlmap.engine.impl.SqlMapClientDelegate=DEBUG
log4j.logger.Java.sql.Connection=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG

其次：springboot开通log4j

mybatis.configuration.log-impl=org.apache.ibatis.logging.stdout.StdOutImpl