## GROUP分组查询和Having子句 有时候我们要进行分组查询，如以下SQL： ``` SELECT * FROM `user` WHERE `id` IN(1637, 1639, 1640 ) GROUP BY name ``` 在BeetlSql中直接拼条件调用group方法，传入字段即可： ``` Query<User> query = sqlManager.query(User.class); List<User> list = query .andIn("id", Arrays.asList(1637, 1639, 1640)) .groupBy("name") .select(); ``` 在分组查询之后，我们可能还要进行having筛选，只需要在后面调用having方法，传入条件即可。 ``` SELECT * FROM `user` WHERE `id` IN( 1637, 1639, 1640 ) GROUP BY name HAVING `create_time` IS NOT NULL ``` ``` Query<User> query = sqlManager.query(User.class); List<User> list = query .andIn("id", Arrays.asList(1637, 1639, 1640)) .groupBy("name") .having(query.condition().andIsNotNull("create_time")) .select(); ```