java - spring data JPA CriteriaBuilder.isNull 返回语法错误

Question

规范:

public Predicate toPredicate(Root<Hotel> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
    Predicate predicate = root.get("starRating").in(s);
            if (unrated) {
                predicate = cb.or(predicate, cb.isNull(root.get("starRating")));
            }
     return predicate;
}

哪里s是 Set .

SQL日志: Hibernate: select hotel0_.hotel_id as hotel_id1_16_, hotel0_.star_rating as star_ra13_16_ where hotel0_.active=? and (hotel0_.star_rating in () or hotel0_.star_rating is null) order by lower(hotel0_.hotel_name) asc

错误: ERROR 6828 --- [nio-8080-exec-1] o.h.engine.jdbc.spi.SqlExceptionHelper : ERROR: syntax error at or near ")"

异常: org.springframework.dao.InvalidDataAccessResourceUsageException: could not extract ResultSet; SQL [n/a]; nested exception is org.hibernate.exception.SQLGrammarException: could not extract ResultSet

我在这里缺少什么？

Answer 1

您的查询中的问题位于:hotel0_.star_ rating in ()。 在此之前对 set 进行空检查:

if(s != null && !s.isEmpty()){
  predicate = root.get("starRating").in(s);
}