JPA查询报错：多匹配标识符行问题排查与解决

问题根源 #

出现More than one row with the given identifier was found错误的核心原因是实体类关联关系与数据库结构不匹配：

• 数据库中account和card是一对多关系（一个账户可对应多张卡片），但你在实体类中错误使用了@OneToOne注解定义关联
• Hibernate会将@OneToOne关联的外键（account_id）视为唯一约束，认为一个账户只能对应一张卡片
• 测试数据中同一账户00000000-0000-0000-0000-000000000ac1下存在多张卡片，当排除ACTIVE状态外的其他状态时，仍有多个匹配记录，触发Hibernate的唯一检查抛出异常；仅ACTIVE状态正常是因为该状态下该账户只有一张卡片，刚好符合@OneToOne的唯一约束

修复步骤 #

1. 修正实体类关联关系 #

将@OneToOne改为符合数据库结构的@ManyToOne和@OneToMany：

修改Card类：

package by.afinny.credit.entity;

import by.afinny.credit.enumeration.CardStatus;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.EnumType;
import javax.persistence.Enumerated;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
import java.util.UUID;

@Entity
@Table(name = "card")
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Builder
public class Card {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private UUID id;
    
    @Enumerated(EnumType.STRING)
    @Column(name = "status", nullable = false, length = 30)
    private CardStatus cardStatus;
    
    // 替换@OneToOne为@ManyToOne，匹配一对多关系
    @ManyToOne(cascade = CascadeType.MERGE)
    @JoinColumn(name = "account_id", referencedColumnName = "id")
    private Account account;
}

修改Account类：

package by.afinny.credit.entity;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import java.util.List;
import java.util.UUID;

@Entity
@Table(name = "account")
@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
@Builder
public class Account {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private UUID id;
    
    // 替换@OneToOne为@OneToMany，关联Card集合
    @OneToMany(mappedBy = "account")
    private List<Card> cards;
}

2. 验证Repository与测试逻辑 #

• CardRepository中的findByAccountIdAndCardStatusNot方法无需修改，Spring Data JPA会自动适配一对多关系的查询
• 修改后测试方法会正确返回该账户下排除指定状态的所有卡片，verifyProperties方法的断言逻辑可正常执行

补充说明 #

数据库中card表的account_id未设置唯一约束，本身就是一对多关系的体现，实体类的关联注解必须与数据库结构完全匹配，否则Hibernate会基于错误的关联规则执行数据加载，导致异常。

内容的提问来源于stack exchange，提问作者Sergey Zolotarev