java - SQL Access 从两个表中选择 NOT IN

Question

您好，我对使用 SQL 语句很陌生，但我的 SQL 语句没有返回正确的结果。 我有两张表 Room(包含房间详细信息)和 Booking(包含预订房间的 ID)。 应检索 Booking 的 RoomID，该 RoomID 不在到达日期和出发日期范围内且 RoomType = single。最后从 Room 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

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可能会非常有帮助。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运行查询:

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 逻辑正确并且能够隔离冲突的预订(因此我不能使用 RmID 值)，那么很明显我想要我的最终结果查询看起来像这样:

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();