簡體   English   中英

在JPA查詢中使用GROUP BY / HAVING子句

[英]Using GROUP BY/HAVING clause in a JPA query

我有兩個與父母/孩子一對多關系的課程:

父母:

@Entity 
@Table(name="RMS.COMMITMENT_REGISTER")
public class CommitmentRegister {

    @Id
    @Column(name="COMMIT_REG_ID")
    private int id;

    @OneToMany(fetch=FetchType.EAGER)
    @JoinColumn(name="COMMIT_REG_ID")
    private List<CommitmentRegisterDetail> details;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public List<CommitmentRegisterDetail> getDetails() {
        return details;
    }

    public void setDetails(List<CommitmentRegisterDetail> details) {
        this.details = details;
    }

}

和孩子:

@Entity 
@Table(name="RMS.COMMITMENT_REGISTER_DETAIL")
public class CommitmentRegisterDetail {

    @Id
    @Column(name="COMMIT_REG_DETAIL_ID")
    private int id;

    @Column(name="AMOUNT")
    private BigDecimal amount;

    @ManyToOne(fetch=FetchType.EAGER)
    @JoinColumn(name="COMMIT_REG_ID")
    private CommitmentRegister commitmentRegister;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public BigDecimal getAmount() {
        return amount;
    }

    public void setAmount(BigDecimal amount) {
        this.amount = amount;
    }

    public CommitmentRegister getCommitmentRegister() {
        return commitmentRegister;
    }

    public void setCommitmentRegister(CommitmentRegister parent) {
        this.commitmentRegister = parent;
    }

}

我想查詢詳細信息總數超過100的CR。我正在使用以下查詢:

    StringBuffer sql = new StringBuffer();

    sql.append( " SELECT CR " );
    sql.append( " FROM CommitmentRegister CR " );
    sql.append( " LEFT JOIN CommitmentRegisterDetail CRD ON ( CRD.commitmentRegister = CR ) ");
    sql.append( " WHERE CR.id >= 91000 " );

    sql.append( " GROUP BY CR " );

    sql.append( " HAVING SUM( CRD.amount ) > 100 " );

    Query q = em.createQuery( sql.toString() );

    return q.getResultList();

但是我收到以下錯誤:

Local Exception Stack: 
Exception [EclipseLink-6015] (Eclipse Persistence Services - 2.4.1.v20121003-ad44345): org.eclipse.persistence.exceptions.QueryException
Exception Description: Invalid query key [amount] in expression.
Query: ReportQuery(referenceClass=CommitmentRegister jpql=" SELECT CR  FROM CommitmentRegister CR  LEFT JOIN CommitmentRegisterDetail CRD ON ( CRD.commitmentRegister = CR )  WHERE CR.id >= 91000  GROUP BY CR  HAVING SUM( CRD.amount ) > 100 ")

在沒有HAVING行的情況下,查詢運行良好,並且將正確的詳細信息分配給了父(CR)。

提前致謝。

表結構(如果相關)

COMMITMENT_REGISTER
    COMMIT_REG_ID

COMMITMENT_REGISTER_DETAIL
    COMMIT_REG_DETAIL_ID
    COMMIT_REG_ID
    AMOUNT

我的猜測是,與HAVING相比,它對連接的處理更多,因為HAVING應該根據EclipseLink文檔工作

也許嘗試這樣的事情,看看進展如何:

StringBuffer sql = new StringBuffer();

sql.append( " SELECT CR " );
sql.append( " FROM CommitmentRegisterDetail CRD " );
sql.append( " LEFT JOIN CRD.commitmentRegister CR ");
sql.append( " WHERE CR.id >= 91000 " );
sql.append( " GROUP BY CRD.commitmentRegister " );
sql.append( " HAVING SUM( CRD.amount ) > 100 " );

Query q = em.createQuery( sql.toString() );

return q.getResultList();

暫無
暫無

聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.

 
粵ICP備18138465號  © 2020-2024 STACKOOM.COM