使用HQL比較兩個表中的記錄

Question

我有兩個名爲Reservation和Vehicle的表。

1. 車輛表有一個車輛ID，它是主鍵。
2. 預約表還有一個車輛ID列，它是一個引用車輛表中的車輛ID的外鍵。我在我的數據庫中指定了外鍵引用。

現在，我想使用HQL檢索其車輛ID不存在於預留表中的車輛的車輛詳細信息。我寫了下面的查詢來實現這一目標：

Query vehicleQuery; 
vehicleQuery = session.getCurrentSession().createQuery("from VehicleBean vbean,ReservationBean rbean where vbean.vehicleID NOT LIKE rbean.vehicleID"); 
     vehicleList=(ArrayList<VehicleBean>) vehicleQuery.list(); 

但是，當運行代碼，我發現了以下錯誤：

Hibernate: select vehiclebea0_.VEHICLEID as VEHICLEID3_0_, reservatio1_.RESERVATIONID as RESERVAT1_5_1_, vehiclebea0_.FAREPERKM as FAREPERKM3_0_, vehiclebea0_.NAME as NAME3_0_, vehiclebea0_.REGISTRATIONNUMBER as REGISTRA4_3_0_, vehiclebea0_.SEATINGCAPACITY as SEATINGC5_3_0_, vehiclebea0_.TYPE as TYPE3_0_, reservatio1_.BOARDINGPOINT as BOARDING2_5_1_, reservatio1_.BOOKINGDATE as BOOKINGD3_5_1_, reservatio1_.BOOKINGSTATUS as BOOKINGS4_5_1_, reservatio1_.DRIVERID as DRIVERID5_1_, reservatio1_.DROPPOINT as DROPPOINT5_1_, reservatio1_.JOURNEYDATE as JOURNEYD7_5_1_, reservatio1_.ROUTEID as ROUTEID5_1_, reservatio1_.TOTALFARE as TOTALFARE5_1_, reservatio1_.USERID as USERID5_1_, reservatio1_.VEHICLEID as VEHICLEID5_1_ from ATA_TBL_VEHICLE vehiclebea0_ cross join ATA_TBL_RESERVATION reservatio1_ where vehiclebea0_.VEHICLEID not like reservatio1_.VEHICLEID 
Jun 04, 2015 9:05:07 AM org.apache.catalina.core.ApplicationDispatcher invoke 
SEVERE: Servlet.service() for servlet jsp threw exception 
java.lang.NumberFormatException: For input string: "vehicleID" 
at java.lang.NumberFormatException.forInputString(Unknown Source) 
at java.lang.Integer.parseInt(Unknown Source) 
at java.lang.Integer.parseInt(Unknown Source) 
at javax.el.ArrayELResolver.coerce(ArrayELResolver.java:166) 
at javax.el.ArrayELResolver.getValue(ArrayELResolver.java:46) 
at org.apache.jasper.el.JasperELResolver.getValue(JasperELResolver.java:104) 
at org.apache.el.parser.AstValue.getValue(AstValue.java:183) 
at org.apache.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:185) 
at org.apache.jasper.runtime.PageContextImpl.proprietaryEvaluate(PageContextImpl.java:1026) 
at org.apache.jsp.WEB_002dINF.views.seevehicles_jsp._jspx_meth_c_005fforEach_005f0(seevehicles_jsp.java:348) 
at org.apache.jsp.WEB_002dINF.views.seevehicles_jsp._jspService(seevehicles_jsp.java:288) 
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728) 
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432) 
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390) 
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:749) 
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:487) 
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:412) 
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:339) 
at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:238) 
at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:264) 
at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1208) 
at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:992) 
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:939) 
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856) 
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:953) 
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:844) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:621) 
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:829) 
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728) 
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) 
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222) 
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123) 
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) 
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171) 
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) 
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) 
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) 
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) 
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023) 
at `enter code here`org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) 
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
at java.lang.Thread.run(Unknown Source) 

這裏是我的POJO類驅動程序和預約：

@Entity 
@Table(name = "ATA_TBL_RESERVATION") 
public class ReservationBean { 
    @Id 
    @Column(name = "RESERVATIONID") 
    private String reservationID; 

    @Column(name = "USERID") 
    private String userID; 

    @Column(name = "ROUTEID") 
    private String routeID; 

    @Column(name = "BOOKINGDATE") 
    private Date bookingDate; 

    @Column(name = "JOURNEYDATE") 
    private Date journeyDate; 

    @Column(name = "VEHICLEID") 
    private String vehicleID; 

    @Column(name = "DRIVERID") 
    private String driverID; 

    @Column(name = "BOOKINGSTATUS") 
    private String bookingStatus; 

    @Column(name = "TOTALFARE") 
    private Double totalFare; 

    @Column(name = "BOARDINGPOINT") 
    private String boardingPoint; 

    @Column(name = "DROPPOINT") 
    private String dropPoint; 


@Entity 
@Table(name = "ATA_TBL_VEHICLE") 
public class VehicleBean { 
    @Id 
    @Column(name = "VEHICLEID") 
    private String vehicleID; 

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

    @Column(name = "TYPE") 
    private String type; 

    @Column(name = "REGISTRATIONNUMBER") 
    private Integer registrationNumber; 

    @Column(name = "SEATINGCAPACITY") 
    private Integer seatingCapacity; 

    @Column(name = "FAREPERKM") 
    private Double farePerKm; 

Answer 1

I found a way to do the same using subquery. Although, I'm not sure out of this and the left join, which one is the more efficient one. 

vehicleQuery = session.getCurrentSession().createQuery("FROM VehicleBean v WHERE (v.type =:vehicleType) AND (v.vehicleID NOT IN (SELECT r.vehicleID FROM ReservationBean r))"); 
      vehicleQuery.setString("vehicleType", vehicleType); 
      vehicleList=(ArrayList<VehicleBean>) vehicleQuery.list(); 

Answer 2

你想要一個左外連接，其中ReservationBean爲null。

vehicleQuery = session.getCurrentSession() 
    .createQuery("from VehicleBean vbean " + 
     " left join vbean.reservation rbean " + 
     " where rbean is null");