找不到能够从 AbstractJPAQuery 转换为 DTO 的转换器

Question

谁能告诉我如何在 JPA 中使用下面的本机查询？现在我收到错误消息，因为找不到转换器。

Sql 查询在 DB(MYSQL)

中给出正确的响应

SELECT SUM(CASE WHEN Status = 'PENDING' THEN 1 ELSE 0 END) AS `pendingRequest`,
       SUM(CASE WHEN Status = 'ACTIVE' or Status ='READY' THEN 1 ELSE 0 END) AS `approvedRequest`,
       SUM(CASE WHEN Status = 'FAILED' THEN 1 ELSE 0 END) AS `rejectedRequest`,
      SUM(CASE WHEN Status = 'ACTIVE' or Status ='READY' or Status ='PENDING' or Status ='FAILED' THEN 1 ELSE 0 END) as totalRequest FROM fiu_consent_db.consent_request;

我在 JPA 存储库中使用的查询

@Query(value = "SELECT SUM(CASE WHEN Status = 'PENDING' THEN 1 ELSE 0 END) AS `pendingRequest`,\n" +
        "       SUM(CASE WHEN Status = 'ACTIVE' or Status ='READY' THEN 1 ELSE 0 END) AS `approvedRequest`,\n" +
        "       SUM(CASE WHEN Status = 'FAILED' THEN 1 ELSE 0 END) AS `rejectedRequest`,\n" +
        "       SUM(CASE WHEN Status = 'ACTIVE' or Status ='READY' or Status ='PENDING' or Status ='FAILED' THEN 1 ELSE 0 END) AS `totalRequest` FROM fiu_consent_db.consent_request",nativeQuery = true)
ConsentRequestCount getAllConsentRequestCount();

我创建的DTO

@Data
@NoArgsConstructor
@AllArgsConstructor
public class ConsentRequestCount {

    private long pendingRequest;
    private long approvedRequest;
    private long rejectedRequest;
    private long totalRequest;


}

我已经为这 4 个文件创建了一个单独的 DTO，并将数据类型设为 long（也尝试使用 int），但它无法映射。

任何人都可以就此提出建议吗？

Answer 1

根据 this，基于 class 的 DTO 预测不适用于本机查询。您可以通过将 DTO class 更改为接口

来切换到基于接口的 DTO 投影

所以这个 DTO：

@Data
@NoArgsConstructor
@AllArgsConstructor
public class ConsentRequestCount {

    private long pendingRequest;
    private long approvedRequest;
    private long rejectedRequest;
    private long totalRequest;

}

改成界面：

public interface ConsentRequestCount {

    long getPendingRequest();
    long getApprovedRequest();
    long getRejectedRequest();
    long getTotalRequest();
}

找不到能够从 AbstractJPAQuery 转换为 DTO 的转换器

no converter found capable of converting from AbstractJPAQuery to DTO

hibernate

jpa

jpql

spring-data-jpa