按不同情况修改表中的值：
@Query(nativeQuery = true, value = "update user u set u.money = (case when :count > u.money then 0 else u.money - :count end) where u.id in(:ids)")
void subGold(@Param("ids") List<Long> ids, @Param("count") Integer count);
将一个表中的值插入到另一个表：
update `order_course` o LEFT JOIN `ir_course` c on c.`id` =o.`course_id` SET o.`begin_time` =c.`begin_time` WHERE o.`begin_time` IS NULL