Question

我有这个实体，它映射用户和工作组之间的关系

package it.prisma.dal.dao.entities.accounting;

import javax.persistence.AttributeOverride;
import javax.persistence.AttributeOverrides;
import javax.persistence.Column;
import javax.persistence.EmbeddedId;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

@Entity
@Table(name = "UserAccount_has_Workgroup")
public class UserAccountHasWorkgroup implements java.io.Serializable {

    private static final long serialVersionUID = 6537213525312531347L;


    private UserAccountHasWorkgroupId id;
    private UserAccount userAccountByUserAccountId;
    private WorkgroupPrivilege workgroupPrivilege;
    private UserAccount userAccountByApprovedByUserAccountId;
    private Workgroup workgroup;
    private boolean approved;


    public UserAccountHasWorkgroup() {
    }

    public UserAccountHasWorkgroup(UserAccountHasWorkgroupId id,
            UserAccount userAccountByUserAccountId,
            UserAccount userAccountByApprovedByUserAccountId,
            Workgroup workgroup, boolean approved) {
        this.id = id;
        this.userAccountByUserAccountId = userAccountByUserAccountId;
        this.userAccountByApprovedByUserAccountId = userAccountByApprovedByUserAccountId;
        this.workgroup = workgroup;
        this.approved = approved;
    }

    public UserAccountHasWorkgroup(UserAccountHasWorkgroupId id,
            UserAccount userAccountByUserAccountId,
            WorkgroupPrivilege workgroupPrivilege,
            UserAccount userAccountByApprovedByUserAccountId,
            Workgroup workgroup, boolean approved) {
        this.id = id;
        this.userAccountByUserAccountId = userAccountByUserAccountId;
        this.workgroupPrivilege = workgroupPrivilege;
        this.userAccountByApprovedByUserAccountId = userAccountByApprovedByUserAccountId;
        this.workgroup = workgroup;
        this.approved = approved;
    }

    @EmbeddedId
    @AttributeOverrides({
            @AttributeOverride(name = "userAccountId", column = @Column(name = "userAccountID", nullable = false)),
            @AttributeOverride(name = "workgroupId", column = @Column(name = "workgroupID", nullable = false)) })
    public UserAccountHasWorkgroupId getId() {
        return this.id;
    }

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

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "userAccountID", nullable = false, insertable = false, updatable = false)
    public UserAccount getUserAccountByUserAccountId() {
        return this.userAccountByUserAccountId;
    }

    public void setUserAccountByUserAccountId(
            UserAccount userAccountByUserAccountId) {
        this.userAccountByUserAccountId = userAccountByUserAccountId;
    }

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "workgroupPrivilegeID")
    public WorkgroupPrivilege getWorkgroupPrivilege() {
        return this.workgroupPrivilege;
    }

    public void setWorkgroupPrivilege(WorkgroupPrivilege workgroupPrivilege) {
        this.workgroupPrivilege = workgroupPrivilege;
    }

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "approvedBy_userAccountID", nullable = false)
    public UserAccount getUserAccountByApprovedByUserAccountId() {
        return this.userAccountByApprovedByUserAccountId;
    }

    public void setUserAccountByApprovedByUserAccountId(
            UserAccount userAccountByApprovedByUserAccountId) {
        this.userAccountByApprovedByUserAccountId = userAccountByApprovedByUserAccountId;
    }

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "workgroupID", nullable = false, insertable = false, updatable = false)
    public Workgroup getWorkgroup() {
        return this.workgroup;
    }

    public void setWorkgroup(Workgroup workgroup) {
        this.workgroup = workgroup;
    }

    @Column(name = "approved", columnDefinition = "bit", nullable = false)
    public boolean isApproved() {
        return this.approved;
    }

    public void setApproved(boolean approved) {
        this.approved = approved;
    }

}

现在我想使用QueryDSL来获取元组的数量。特别是我有这个QueryDSL查询

JPAQuery query =  new JPAQuery(getEntityManager()).from(userAccountHasWorkgroup)
                .where(userAccountHasWorkgroup.userAccountByUserAccountId.id
                        .eq(userAccountId));

其中userAccountHasWorkgroup是QueryDSL的QUserAccountHasWorkgroup实例。如您所见，查询是在一个字段上运行的，该字段是实体密钥的一部分。以上查询在以下JPA查询

中进行了翻译

select userAccountHasWorkgroup
from UserAccountHasWorkgroup userAccountHasWorkgroup
where userAccountHasWorkgroup.userAccountByUserAccountId.id = ?1

我尝试运行代码：

query.count()

问题是此代码引发了以下异常

http://pastebin.com/C9kEHqHp

实体正确引用数据库中的表。

可能是什么问题？

谢谢

Query列上的QueryDSL count（）问题

0 个答案: