mysql外键问题

几天查询数据库发现【用户表pub_user】里面的垃圾数据太多，于是准备删掉。但是删除时发现删不了，因为有一张表的外键与【用户表pub_user】相关联。于是手动在navicat删除了该表的外键。于是表【用户表pub_user】中的垃圾数据可以正常删除，再次手动还原外键时发现建不了。报错如下

问题解决：是因为删除【用户表pub_user】表中的数据后，外键表中的部分数据有的外键不在【用户表pub_user】中了。删掉了这写数据后即可新建外键了。

建立表外键关联

用户角色映射表。外键为角色id 与角色表中的字段相关联。

package com.comtop.map.store.uom.entity;

import com.comtop.map.store.entity.BaseEntity;
import com.fasterxml.jackson.annotation.JsonIgnore;
import org.hibernate.annotations.GenericGenerator;
import javax.persistence.*;

@Entity
@Table(name = "pub_user_role")
public class UserRoleEntity extends BaseEntity{

    /** 主键id */
    @Id
    @GeneratedValue(generator = "CustomIDGen")
    @GenericGenerator(name = "CustomIDGen", strategy = "com.comtop.map.store.core.id.CustomIDGen")
    private Long id;

    /** 用户编号 */
    @Column
    private Long userId;

    /** 角色编号 */
    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "role_id")
    @JsonIgnore
    private RoleEntity role;

    public Long getId() {
        return id;
    }

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

    public Long getUserId() {
        return userId;
    }

    public void setUserId(Long userId) {
        this.userId = userId;
    }

    public RoleEntity getRole() {
        return role;
    }

    public void setRole(RoleEntity role) {
        this.role = role;
    }
}

角色表

package com.comtop.map.store.uom.entity;

import com.comtop.map.store.entity.BaseEntity;
import org.hibernate.annotations.GenericGenerator;
import javax.persistence.*;
import java.util.List;

@Entity
@Table(name = "pub_role")
public class RoleEntity extends BaseEntity{

    /** 角色编号 */
    @Id
    @GeneratedValue(generator = "CustomIDGen")
    @GenericGenerator(name = "CustomIDGen", strategy = "com.comtop.map.store.core.id.CustomIDGen")
    private Long roleId;

    /** 角色名 */
    @Column(length = 50)
    private String roleName;

    /** 备注 */
    @Column(length = 500)
    private String remarks;

    @Transient
    private String [] perms;

    @Transient
    private List<UserRoleEntity> users;

    public Long getRoleId() {
        return roleId;
    }

    public void setRoleId(Long roleId) {
        this.roleId = roleId;
    }

    public String getRoleName() {
        return roleName;
    }

    public void setRoleName(String roleName) {
        this.roleName = roleName;
    }

    public String getRemarks() {
        return remarks;
    }

    public void setRemarks(String remarks) {
        this.remarks = remarks;
    }

    public String[] getPerms() {
        return perms;
    }

    public void setPerms(String[] perms) {
        this.perms = perms;
    }

    public List<UserRoleEntity> getUsers() {
        return users;
    }

    public void setUsers(List<UserRoleEntity> users) {
        this.users = users;
    }
}

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