'How to delete a record (string) JAVA and MYSQL
I successfully can delete an integer but when I tried to make it a STRING it says "unknown column itemtodelete in where clause but my ITEMTODELETE is a STRING declared in the database not an integer how much It doesn't delete a STRING?
below is my code:
private void DeleteButtonActionPerformed(java.awt.event.ActionEvent evt) {
int del = (prompt):
if (del == JOptionPane.YES_OPTION){
DelCurRec();
}
}
public void DelCurRec() {
String id = field.getText();
String SQL = "DELETE FROM inventory WHERE ItemCode = "+id+" ";
try {
Class.forName(connectio);
} catch (Exception e) {
JOptionPane.showMessageDialog(null,""+e.getMessage(),"JDBC Driver Error",JOptionPane.WARNING_MESSAGE);
}
Statement stmt = null;
Connection con = null;
//Creates connection to database
try {
con = DriverManager.getConnection("Connection");
stmt = con.createStatement();
} catch (Exception e) {
JOptionPane.showMessageDialog(null,""+e.getMessage(),"Connection Error",JOptionPane.WARNING_MESSAGE);
}
//Execute the SQL statment for deleting records
try {
stmt.executeUpdate(SQL);
//This closes the connection to the database
con.close();
//This closes the dialog
JOptionPane.showMessageDialog(null,"Deleted Succesfully","Delete Successful",JOptionPane.WARNING_MESSAGE);
} catch (Exception e) {
JOptionPane.showMessageDialog(null,""+e.getMessage(),"Communication Error",JOptionPane.WARNING_MESSAGE);
}
}
Solution 1:[1]
Do NOT use a Statement use a PreparedStatement instead, otherwise your application will be vulnerable to SQL injections. E.g. someone enters a string like: "'; drop table inventory; --"
The corresponding prepared statment would look something like:
String SQL = "DELETE FROM inventory WHERE ItemCode = ? ";
PreparedStatement pstmt = null;
// get a connection and then in your try catch for executing your delete...
pstmt = con.prepareStatement(SQL);
pstmt.setString(1, id);
pstmt.executeUpdate();
Solution 2:[2]
I think you need to pass Integer.parseInt(id) and not id...assuming your id is int
Solution 3:[3]
This worked for me:
Statement stmt=con.createStatement();
stmt.executeUpdate("DELETE FROM student WHERE reg_number='R18854';");
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | Emil H |
| Solution 2 | Shashank Kadne |
| Solution 3 | procrastinator |
