SQL Access从两个表中选择NOT IN

Question

您好，我是使用SQL语句的新手，我的SQL语句未返回正确的结果。 我有两个表“房间”（包含“房间详细信息”）和“预订”（包含“已预订的房间ID”）。 应该检索预订的RoomID，该ID不在到达日期和出发日期的范围内，并且RoomType = single。 最后，从“房间”表中搜索ID以显示详细信息。

psmt = con.prepareStatement("SELECT RmID,RmName,RmType,RmDescription,RmRate,RmMaxPerson FROM Room WHERE RmID NOT IN (SELECT RmID FROM Booking WHERE ((BookArrivalDate >= ? AND BookArrivalDate < ?))) AND RmType = ?");
psmt.setDate(1, sqlDateAStart);
psmt.setDate(2, sqlDateAEnd);
psmt.setString(3, RoomType);
rs = psmt.executeQuery()

谢谢

Answer 1

您在不考虑离开日期时遇到错误，请尝试以下操作：

SELECT 
RmID,
RmName,
RmType,
RmDescription,
RmRate,RmMaxPerson 
FROM 
Room r
INNER JOIN Booking b on (r.RmID =b.RmID ) 
WHERE BookArrivalDate < ? AND BookDepartureDate > ? AND RmType = ?

Answer 2

您必须更改下面的代码以从两个表中选择值，并且您正在处理同时需要日期和时间的预订系统，因此我建议您将Timestamp用作BookArrivalDate和BookDepartureDate的数据类型。 我已经发布了一个SQL查询，该查询将检查给定的FromDate和ToDate是否存在于任何预定日期之间，如果有，则返回结果。

SELECT RmID,RmName,RmType,RmDescription,RmRate,RmMaxPerson
FROM Room,Booking
WHERE 
(RmType ='single') 
AND 
((
('fromtime'>=arrivaltime)
AND 
('totime'<=departuretime))
OR 
(
('fromtime'<=arrivaltime)
 AND 
 ('totime'>=departuretime))
OR 
(
('fromtime'<=arrivaltime) 
AND 
('totime'>=arrivaltime)) 
OR 
(
('totime'>=arrivaltime)
 AND
  ('totime'<=departuretime)) 
OR 
(
('totime'>=departuretime)
 AND
  ('fromtime'<=departuretime))
OR 
(
('fromtime'>=arrivaltime)
 AND
  ('fromtime'<=departuretime)
)) 

在这里， 到达时间是数据库中存在的BookArrivalDate ，而离开时间是数据库中存在的BookDepartureDate 。 fromtime＆totime是您在准备好的语句/日期范围内提供的值。

Answer 3

在这种情况下，隔离应用程序的特定部分并使用一些测试程序对其进行试验会非常有帮助。 例如，我在Access中创建了一个[Booking]表。

BookingID  RmID  BookArrivalDate  BookDepartureDate
---------  ----  ---------------  -----------------
        1   101  2013-10-21       2013-10-23       
        2   102  2013-11-01       2013-11-03       

...然后使用以下小测试程序对其执行查询：

import java.sql.*;
import org.joda.time.*;

public class JDBCQuery {
    public static void main(String args[]) {
        Connection conn = null;
        PreparedStatement s = null;
        try {
            Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
            conn = DriverManager.getConnection(
                    "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb, *.accdb)};" + 
                    "DBQ=C:\\Users\\Public\\Database1.accdb;");

            LocalDate requestedArrivalDate = LocalDate.parse("2013-10-12");
            LocalDate requestedDepartureDate = LocalDate.parse("2013-10-21");

            s = conn.prepareStatement(
                    "SELECT BookingID, RmID FROM Booking WHERE BookDepartureDate > ? AND BookArrivalDate < ?");
            s.setDate(1, new java.sql.Date(requestedArrivalDate.toDate().getTime()));
            s.setDate(2, new java.sql.Date(requestedDepartureDate.toDate().getTime()));
            ResultSet rs = s.executeQuery();

            System.out.println(String.format("Requested arrival: %s", requestedArrivalDate.toString()));
            System.out.println(String.format("Requested departure: %s", requestedDepartureDate.toString()));
            System.out.println("The following bookings conflict with that request...");
            if (rs!=null) {
                while (rs.next()) {
                    System.out.println(String.format("BookingID: %d, RmId: %d", rs.getInt("BookingID"), rs.getInt("RmID")) );
                }
            }
            System.out.println("(end of list)");

        } catch( Exception e ) {
            e.printStackTrace();
        } finally {
            try {
                if (s != null) {
                    s.close();
                }
                if (conn != null) {
                    conn.close();
                }
            } catch( Exception e ) {
                e.printStackTrace();
            }
        }
    }
}

一旦我确信我的SQL逻辑正确并能够隔离冲突的预订（以及因此无法使用的RmID值），那么很显然，我希望我的最终查询看起来像这样：

SQL = 
        "SELECT RmID FROM Room " +
        "WHERE " + 
            "RmID NOT IN " +
                "(" +
                    "SELECT RmID FROM Booking " +
                    "WHERE BookDepartureDate > ? AND BookArrivalDate < ? " +
                ")" +
            "AND RmType = ?";
s = conn.prepareStatement(SQL);
s.setDate(1, new java.sql.Date(requestedArrivalDate.toDate().getTime()));
s.setDate(2, new java.sql.Date(requestedDepartureDate.toDate().getTime()));
s.setString(3, "Single");
ResultSet rs = s.executeQuery();