QueryDSL与SpringDataJPA复杂查询

1、嵌套子查询

例如实现sql： select u.* from user where u.id in (select s.id from student s where s.status = 0)

var query = from(user )
        .where(user.id.`in`(JPAExpressions
                .select(student.id)
                .from(student)
                .where(student.status = 0))

2、按照日期进行模糊查询

按照日期的月日查询

例如    2018-03-05在2020-03-01和2020-03-31之间

val dateFormat = SimpleDateFormat("MM-dd")
val dateExpr = Expressions.stringTemplate("DATE_FORMAT({0},'%m-%d')", QUser.user.birthDay)
val today = dateFormat.format(Date())
val predicate = QUser.user.status.eq(UserStatus.VALID)
                .and(dateExpr.gt("03-01")).and(dateExpr.le(today))