DELETE查询未从数据库表中删除

Question

I'm new to JSP and I'm trying to create a web interface where a user can enter information that they want to deleted and it will delete in the database table.

Here they should enter the student_id and the course_id , and then any data that have the 2 specified id's should be deleted. however, it is not deleting from the table. I'm getting an exception

array index out of bounds

Here is my code:

Delete Row where Student ID: <input type="text" name="dStudent">
and Course ID: <input type="text" name="dCourse">
<input type ="submit" value="Delete">

String delCourse = request.getParameter("dCourse");
String delStudent = request.getParameter("dStudent");

if(delCourse != null && delCourse.length() > 0 && delStudent != null && delCourse.length() > 0){
    statement.executeUpdate("DELETE FROM enroll WHERE student_id = '" + Integer.parseInt(delStudent) + "' AND course_id = '" + Integer.parseInt(delCourse));
}

Answer 1

You're not closing the single quote after Integer.parseInt(delCourse), that could be an issue. Of course, to be a lot safer you should use a PreparedStatement ( http://docs.oracle.com/javase/tutorial/jdbc/basics/prepared.html ) and pass integer values via setInt.