Springboot JPA 實體類添加@Transient

• Hibernate

在實體類與數據庫表建立映射關系時添加 @Table 注解, 當表中不存在實體類中的某個屬性的時候, 就需要用到 @Transient 注解

• 用法: 添加在需要忽略的實體類屬性上

@Transient
private String columeName;

• 實體類

import com.fasterxml.jackson.annotation.JsonIgnore;
import jdk.nashorn.internal.ir.annotations.Ignore;
import lombok.Data;
import javax.persistence.*;

@lombok.Data
@Entity
public class UserMonitorStationMapping {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;
    
    private Integer monitorStationId;
    
    @Transient
    private String shortName;        // TODO 數據庫表中無此字段

    @ManyToOne
    @JsonIgnore
    private User user;
}

• 數據庫表結構
  

org.hibernate.exception.SQLGrammarException: could not extract ResultSet
at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:82)
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter
.java:49)at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:124)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:109)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:88)
at org.hibernate.loader.Loader.getResultSet(Loader.java:2062)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1859)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1838)
at org.hibernate.loader.Loader.doQuery(Loader.java:906)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:348)
at org.hibernate.loader.Loader.doList(Loader.java:2550)
at org.hibernate.loader.Loader.doList(Loader.java:2536)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2366)
at org.hibernate.loader.Loader.list(Loader.java:2361)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:495)
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:357)
at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:198)
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1230)
at org.hibernate.internal.QueryImpl.list(QueryImpl.java:101)
at com.bbs.dao.BaseDao.list(BaseDao.java:82)
at com.bbs.dao.BaseDao.list(BaseDao.java:92)
at com.bbs.service.impl.OrderServiceImpl.selectOrdersByOne(OrderServiceImpl.java:35)
at com.bbs.service.impl.OrderServiceImpl

• 解決方法

在實體類上添加 @Transient 注解