Hql 子句在子句 case 中为空，不像在 mysql 中那样工作答案

【问题标题】：Hql clause is null in clause case , not working as in mysqlHql 子句在子句 case 中为空，不像在 mysql 中那样工作
【发布时间】：2014-09-02 13:23:49
【问题描述】：

我在mysql中做了一个查询。

SELECT COALESCE(SUM(t2.ammout * CASE WHEN t2.idAccountDeb = :accountSelec AND  
(t2.idAccountDeb <> t2.idAccountCred OR t2.idAccountCred IS NULL) 
THEN 1 WHEN t2.idAccountCred = :accountSelec AND
(t2.idAccountDeb <> t2.idAccountCred OR t2.idAccountDeb IS NULL) THEN
-1 ELSE 0 END),0) FROM TransactionAccount t2 WHERE 
(t2.idAccountDeb = :accountSelec OR t2.idAccountCred = :accountSelec) AND
t2.dtInf <= :dateSelec

我尝试在 Hql 中转换

SELECT COALESCE(SUM(t2.ammout * CASE WHEN t2.accountDeb = :accountSelec AND 
(t2.accountDeb <> t2.accountCred OR t2.accountCred IS NULL) THEN 1
WHEN t2.accountCred = :accountSelec AND (t2.accountDeb <> t2.accountCred OR
t2.accountDeb IS NULL) THEN -1 ELSE 0 END),0) FROM TransactionAccount t2 
WHERE   (t2.accountDeb = :accountSelec OR t2.accountCred = :accountSelec) 
AND t2.dtInf <= :dateSelec

但是在 hql 中返回 0.00，这个 END),0) 。在 mysql 中，150.97。

当帐户借方或帐户贷方为空时，会发生这种情况。

我做错了什么？例子：如果交易中有一个账户贷方或借方账户值为空，则查询不能在“为空”子句中捕获。

我的豆子：

    @Entity
    public class Account implements Serializable {
    @Id
    @GeneratedValue
    private long id;
    @Column(length = 40)
    private String cod;
    private boolean credit;
    private String name;//CTA
    @OneToOne
    @JoinColumn(name = "idCompany")
    private Company company;


    @Version
    private int version;

    //getter and setters
}

    @Entity
    public class Transaction implements Serializable {
    @Id
    @GeneratedValue
    private long id;
    private String history;
    @JoinColumn(name = "idAccountDeb")
    @OneToOne
    private Account accountDeb;
    @JoinColumn(name = "idAccountCred")
    @OneToOne
    private Account accountCred;
    private BigDecimal ammount;
    @Temporal(TemporalType.DATE)
    private Date dtInf;
    @Temporal(TemporalType.TIMESTAMP)
    private Date dtPosted;
    @Temporal(TemporalType.TIMESTAMP)
    private Date dtModif;  
    private TypeTransaction type;
    @Version
    private int version;
}

【问题讨论】：

我不确定，但我不认为（例如）THEN -1 ELSE 0 END 是有效的 HQL（但当然，我可能是错的......）
如果交易中有一个账户贷方或借方账户值为空，则查询不能在“为空”子句中捕获。

标签： java mysql hql

【解决方案1】：

我的解决方案。

只需将 id 放在比较帐户中

新查询：

SELECT COALESCE(SUM(t2.ammount * CASE WHEN t2.accountDeb.id = :accountSelec 
           AND (t2.accountDeb.id <> t2.accountCred.id OR t2.accountCred.id is null) THEN 1
           WHEN  (t2.accountDeb.id <> t2.accountCred.id 
           OR t2.accountDeb.id is null) THEN -1 ELSE 0 END),0)
           FROM TransactionAccount t2 WHERE (t2.accountDeb = :accountSelec 
           OR t2.accountCred = :accountSelec) AND t2.dtInf <= :dateSelec

【讨论】：