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mysql - spring mysql hibernate中的外键引用

转载 作者：行者123 更新时间：2023-11-29 12:53:44 26 4
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嗨，我正在编写一个 spring mvc 休眠注释应用程序，我有 2 个表 "team" 和另一个表 "players"。这里我使用 一个-对一映射和mysql数据库。在玩家表中，我保存玩家记录，如姓名、活跃年份等。“团队” 表包含两个条目teamid(主键)和teamname。“players” 表包含外键 teamid。在这里，当我尝试删除团队名称而不删除 players 表中的所有引用时，我是获取错误消息

HTTP Status 500 - Request processing failed; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute update query

所以当我删除所有引用时，就没有错误了。那么我如何在删除之前找到所有引用。我有兴趣使用 javascript 显示一条警告消息，警告删除所有引用。我知道如何创建javascript中的简单警报消息，但在这里我必须仅在存在外键引用时才显示警报。我想知道是否有其他方法可以删除外键引用而不影响“玩家” 表。

AddTeam.java


@Entity
@Table(name="Team")

public class AddTeam {


    @Id
    @Column(name="teamId")

    private Integer teamId;

    @Column(name="teamName")
    private String teamName;

    public Integer getTeamId() {
          return teamId;
         }

         public void setTeamId(Integer teamId) {
          this.teamId = teamId;
         }

         public String getTeamName() {
          return teamName;
         }

         public void setTeamName(String teamName) {
          this.teamName = teamName;
         }

}

Player.java

@Entity
@Table(name="playerdata")
public class Player implements Serializable {

    private static final long serialVersionUID = -723583058586873479L;

    /**
     * 
     */

    @Id
    @Column(name="playerid")
    private Integer playerId;

    @Column(name="playername")
    private String playerName;

    @Column(name="yearsactive")
    private Integer yearsActive;

        @Column(name="country")
    private Integer Country;




     @OneToOne
     @JoinColumn(name="teamId")
     private AddTeam teams;



    public Integer getPlayerId(){
        return playerId;
    }
    public void setPlayerId(Integer playerId){
        this.playerId=playerId;
    }


    public String getPlayerName(){
        return playerName;
    }
    public void setPlayerName(String playerName){
        this.playerName=playerName;
    }



    public String getCountry(){
        return Country;
    }
    public void setCountry(String Country){
        this.Country=Country;
    }



    public Integer getyearsActive(){
        return yearsActive;
    }
    public void setyearsActive(Integer yearsActive){
        this.yearsActive=yearsActive;
    }

    public AddTeam getTeams() {
          return teams;
         }

         public void setTeams(AddTeam teams) {
          this.teams = teams;
         }
  }

这是在playerDaoImplementation.java类中使用的查询

  @Override
    public void deleteResource(int playerid) {
        // TODO Auto-generated method stub
        sessionfactory.getCurrentSession().createQuery("DELETE FROM Resource WHERE playerid=" +playerid).executeUpdate();


    }

AddteamDaoImplementation.java中用于删除的查询

@Override
    public void deleteTeams(int teamid) {
        // TODO Auto-generated method stub
        sessiofactory.getCurrentSession().createQuery("DELETE FROM AddTeam WHERE teamid="+teamid).executeUpdate();

    }

PlayerController.java 中的删除函数

@RequestMapping(value="/deletePlayer",method=RequestMethod.GET)
    public ModelAndView deletePlayerDetails(@ModelAttribute("command")  Player player,
            BindingResult result){
        playerService.deletePlayer(player.getPlayerId());
        Map<String, Object> model = new HashMap<String, Object>();
        model.put("playerkey", playerService.listPlayer());
        model.put("teamKey", addteamService.listTeams());
        return new  ModelAndView("EditPlayer",model);
    }

团队.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
      <%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%>

    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Players Manager</title>

<center>
<h2>Add Team Details</h2>
<form:form method="POST" action="Team.html">
   <table>
                <tr>
                    <td><form:label path="teamId">Team ID:</form:label></td>
                    <td><form:input path="teamId" id="demo" value="${team.teamId}"/></td>
                </tr>
                <tr>
                    <td><form:label path="teamName">Team Name:</form:label></td>
                    <td><form:input path="teamName" value="${team.teamName}"/></td>
                </tr>

                <tr>
                <tr>
                    <td>&nbsp;</td>
                  <td><input type="submit" value="SAVE"/></td>
                </tr>
            </table> 
        </form:form>
        <br/>
  <c:if test="${!empty teamKey}">
    <table align="center" border="1">
        <tr>
            <th>Category ID</th>
            <th>Category Name</th>
            <th>Options</th>
        </tr>

        <c:forEach items="${teamKey}" var="team">
            <tr>
                <td><c:out value="${team.teamId}"/></td>
                <td><c:out value="${team.teamName}"/></td>
                <td align="center"><a href="editTeam.html?teamId=${team.teamId}">Edit</a> |
                 <a href="deleteTeam.html?teamId=${team.teamId}">Delete</a></td>
            </tr>
        </c:forEach>
    </table>
</c:if>
<h2><a href="updateresource.html">Adding Publication</a></h2>


</center>



</body>
</html>

EditPlayer.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>

    <%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
     <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Resource Manager</title>
</head>
<body>

<center>
<h2>Add Players</h2>
<form:form method="POST" action="save.html">
<table>
  <tr>
    <td><form:label path="playerId">Player Id</form:label></td>
    <td><form:input path="playerId"  value= "${player.playerId }"/></td>
  </tr>
  <tr>
    <td><form:label path="playerName">Name</form:label></td>
    <td><form:input path="playerName" value="${player.playerName }"/></td>
  </tr>

  <tr>
    <td><form:label path="YearsActive">Experience</form:label></td>
    <td><form:input path="YearsActive" value="${player.YearsActive }"/></td>
  </tr>
   <tr>
    <td><form:label path="Country">Date of Join</form:label></td>
    <td><form:input path="Country" value="${player.Country }"/></td>
  </tr>




    <tr>
                    <td>
                        <form:label path="teams.teamId">Team Name</form:label>
                    </td>
                    <td>
                        <form:select path="teams.teamId" cssStyle="width: 150px;">    
                            <option value="-1">Select a type</option>
                            <c:forEach items="${teamKey}" var="teams">
                            <option value="${teams.teamId}">${teams.teamName}</option>
                            </c:forEach>
                        </form:select>
                    </td>
                </tr>
                <tr>



  <tr>
   <td colspan="2"><input type="submit"value="Submit"></td>

    </tr>

 </table>
 </form:form>
<br/>

 <c:if test="${!empty playerkey}">
    <table align="center" border="1">
        <tr>
            <th>Player ID</th>
            <th>Player Name</th>
            <th>YearsActive</th>
            <th>Country</th>

        </tr>

        <c:forEach items="${playerkey}" var="player">
            <tr>
                <td><c:out value="${player.playerId}"/></td>
                <td><c:out value="${player.playerName }"/></td>
                <td><c:out value="${player.YearsActive}"/></td>
                <td><c:out value="${player.Country}"/></td>



                <td align="center"><a href="editPlayerDetails.html?playerId=${player.playerId}">Edit</a> | <a href="deletePlayer.html?playerId=${player.playerId}">Delete</a></td>
            </tr>
        </c:forEach>
    </table>
</c:if>

    <h2><a href="addTeam.html">Adding Team</a></h2>
</center>
</body>
</html>

请帮忙。提前致谢

最佳答案

对于您的用例，您的数据库建模(如果您已经定义了架构)或实体建模(如果您从实体模型生成架构)不正确。外键应位于指向 Player 主键的 AddTeam 表中。就实体映射而言，OneToOne 应该位于 AddTeam 上。

关于mysql - spring mysql hibernate中的外键引用，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/24400126/

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