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Java 使用QueryDSL JPA在MySQL中查找重复的行_Java_Mysql_Jpa_Querydsl - Fatal编程技术网

Java 使用QueryDSL JPA在MySQL中查找重复的行

Java 使用QueryDSL JPA在MySQL中查找重复的行,java,mysql,jpa,querydsl,Java,Mysql,Jpa,Querydsl,我想在QueryDSL JPA中执行这个SQL请求 SELECT authorizationitem.* FROM authorizationitem INNER JOIN ( SELECT `authorize` FROM authorizationitem GROUP BY `authorize` HAVING COUNT(*)>1 ) a2 ON authorizationitem.`authorize` = a2.`author

我想在QueryDSL JPA中执行这个SQL请求

SELECT authorizationitem.* 
FROM authorizationitem 
INNER JOIN 
(
    SELECT `authorize` 
    FROM authorizationitem 
    GROUP BY `authorize` 
    HAVING COUNT(*)>1
) a2 
    ON authorizationitem.`authorize` = a2.`authorize`;
为了在表中找到重复的行,我应该执行这个请求。但是使用QueryDSL,我找不到写这篇文章的方法

QueryDSL似乎不允许在内部联接中使用子查询:s

有什么建议吗

谢谢
关于,

您可以尝试在WHERE子句中使用子查询,但其效率可能低于FROM子句中的子查询。确保authorizationitem.Authorization上有索引以优化联接和分组依据

SELECT authorizationitem.* 
FROM authorizationitem 
WHERE EXISTS (
    SELECT `authorize` 
    FROM authorizationitem2 
   WHERE authorizationitem2.authorize = authorizationitem.authorize
    GROUP BY `authorize` 
    HAVING COUNT(*)>1
);


您可以尝试在WHERE子句中使用子查询,但其效率可能低于FROM子句中的子查询。确保authorizationitem.Authorization上有索引以优化联接和分组依据

SELECT authorizationitem.* 
FROM authorizationitem 
WHERE EXISTS (
    SELECT `authorize` 
    FROM authorizationitem2 
   WHERE authorizationitem2.authorize = authorizationitem.authorize
    GROUP BY `authorize` 
    HAVING COUNT(*)>1
);


你不能用HQL/JPQL来表达这一点,所以你需要用SQL来表达这一点。Querydsl JPA提供了通过其API表达JPQL和SQL查询的可能性。

您不能用HQL/JPQL来表达这一点,因此您需要用SQL来表达这一点。Querydsl JPA提供了通过其API表达JPQL和SQL查询的可能性。

Hi Timo,你能给我举个例子吗?我不知道该怎么办。Thanksher是Hi Timo参考文件的相关部分,你能给我举个例子吗?我不知道该怎么办。Thanksher是参考文档的相关部分