我收到以下MySQL异常:
这是什么意思,我该如何解决?
这是负责此异常的代码:
public void actionPerformed(ActionEvent e) {
list.clearSelection();
String selectString = " ";
String afName = auth_fName.getText();
String aMI = auth_MI.getText();
String alName = auth_lName.getText();
String tField = titleField.getText();
String sField = subjectField.getText();
try {
Connection conn = Database.getConnection();
Statement s = conn.createStatement();
if (!afName.equals("") && (!aMI.equals("")) && (!alName.equals("")) && (!tField.equals("")) && (!sField.equals(""))) {
selectString = "SELECT a.call_Number as callNbr "
+ "FROM book a "
+ "FULL JOIN transaction b "
+ "ON a.call_Number=b.call_Number";
}
s = conn.createStatement();
System.out.println(selectString);
ResultSet rs = s.executeQuery(selectString);
while (rs.next()) {
String call_Num = rs.getString("call_Number");
String title = rs.getString("title");
String auth_lName = rs.getString("auth_lName");
String auth_MI = rs.getString ("auth_MI");
String auth_fName = rs.getString("auth_fName");
String availability = rs.getString("availability");
view = new View(call_Num, title, auth_lName, auth_MI, auth_fName, availability);
vList.add(view);
System.out.println(view);
}
rs.close();
s.close();
conn.close();
list.setListData(vList.toArray());
} catch (Exception ex) {
ex.printStackTrace();
}
}
这是DDL和内容:
s.executeUpdate (
"CREATE TABLE book ("
+ "call_Number CHAR(10),"
+ "PRIMARY KEY (call_Number),"
+ "auth_fName CHAR(30)NOT NULL, auth_MI CHAR(2),"
+ "auth_lName CHAR(50)NOT NULL, title CHAR(100) NOT NULL,"
+ "subject CHAR(30) NOT NULL)");
count = s.executeUpdate (
"INSERT INTO book"
+ " VALUES"
+ "('MY.111.000', 'Mark', 'M','Bradshaw','Mystery Under the Sun','mystery'),"
+ "('MY.111.001', 'Mark','','Twain','The Adventures of Huckleberry Finn','mystery'),"
+ "('SF.111.002', 'Kito', 'M','Bradford','Mr. Roboto','science fiction'),"
+ "('SF.111.003', 'Eric','','Laslow','Science Fiction - Can It Happen?','science fiction'),"
+ "('AV.111.004', 'Rashad','','Cheeks','Fire Under the Bridge','adventure'),"
+ "('AV.111.005', 'Samantha','A','Appleby','The Open Sea','adventure'),"
+ "('CO.111.006', 'Lindsey', '','Butterby','What? We cant spend anymore!?','comedy'),"
+ "('CO.111.007', 'Judy', 'S','Yates','So this is life?','comedy'),"
+ "('IN.111.008', 'Elizabeth', 'J','Lee','Mystery Under the Sun','international'),"
+ "('IN.111.009', 'Gabriella', 'M','Rodriguez','Love in Brazil','international')");
****** * t_action table * **************************
//create transaction table
s.executeUpdate (
"CREATE TABLE t_action ("
+ "patron_ID CHAR(10) NOT NULL,"
+ "call_Number CHAR(10) NOT NULL, check_Out_Date DATE NOT NULL, check_In_Date DATE NOT NULL,"
+ "PRIMARY KEY (patron_ID, call_Number),"
+ "avail CHAR(15), total_Charge FLOAT)");
count3 = s.executeUpdate (
"INSERT INTO t_action"
+ " VALUES"
+ "('P222200000','MY.111.000','2011-03-08','2011-03-15','AVAILABLE',5.00),"
+ "('P222200001','MY.111.001','2011-03-31','2011-04-6','DUE 2011-04-6',5.00),"
+ "('P222200002','SF.111.002','2011-03-30','2011-04-5','DUE 2011-04-5',5.00),"
+ "('P222200003','SF.111.003','2011-03-29','2011-04-4','DUE 2011-04-4',5.00),"
+ "('P222200004','AV.111.004','2011-03-28','2011-04-3','DUE 2011-04-3',5.00),"
+ "('P222200005','AV.111.005','2011-03-27','2011-04-2','DUE 2011-04-2',5.00),"
+ "('P222200006','CO.111.006','2011-03-26','2011-04-1','DUE 2011-04-1',5.00),"
+ "('P222200007','CO.111.007','2011-01-06','2011-01-12','AVAILABLE',5.00),"
+ "('P222200008','IN.111.008','2011-02-06','2011-02-12','AVAILABLE',5.00),"
+ "('P222200009','IN.111.009','2011-03-06','2011-03-12','AVAILABLE',5.00)");
最佳答案
使用如下的<column> as
谓词:-selectString = "SELECT a.call_Number as callNbr, ... " + "FROM book a" + "FULL JOIN transaction b" + "ON a.call_Number=b.call_Number";
然后更改代码以查找callNbr
:-String call_Num = rs.getString("callNbr");
HTH。