com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Expression #2 of SELECT list is not in GROUP BY clause and contains nonaggregated column 'col_user_6.a.START_TIME' which is not functionally dependent on columns in GROUP BY clause; this is incompatible with sql_mode=only_full_group_by

解决方法 ：执行SET GLOBAL sql_mode = ''; 把sql_mode 改成非only_full_group_by模式。验证是否生效SELECT @@GLOBAL.sql_mode 或SELECT @@sql_mode

SET sql_mode ='STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION';

官方文档https://dev.mysql.com/doc/refman/5.7/en/group-by-handling.html