Monday, May 24, 2010

Delete a Specific Row from a Database Table

Consider a case where we are creating a table and we have to add some data in it. It may happen that we might add a wrong data in a row, now we need to delete that wrong data. This can be done very easily, and in this section we are going to do the same that is, how to delete a specific row from a specific database table. Here is an example with code which provides the facility for deleting specific row in a database table. Sometimes, you want to delete a specific row then you use some java methods and APIs interfaces. Detail information given below:

Description of program:

Firstly, in this program we are going to establish the connection by using MySQL database. After establishing the connection we are going to delete a specific row from the table. If the row get deletes successfully then it will shows an appropriate message: "Row is deleted.". If the row doesn't gets deleted then displays a message: "Row is not deleted". If there arises any problem while establishing the connection or there doesn't exist the table by that name or there is no data in the table then the exception will be thrown that "SQL statement is not executed". If any problems occurs while making connection then system displays a message with the help of java.lang.ClassNotFoundException exception.

Description of code:

DELETE FROM employee6 WHERE Emp_code = '1':
Above code deletes the record in the employee6 table which has Emp_code = '1'.
employee6: This is a table name of a specific database.
Emp_code: It specifies the column name of a specific database table.
'1': This is the value of specified column name.

Here is the code of program:

import java.sql.*;

public class DeleteSpecificRow{
public static void main(String[] args) {
System.out.println("An example for Deleting a Row from a Database!");
Connection con = null;
String url = "jdbc:mysql://localhost:3306/";
String driver = "com.mysql.jdbc.Driver";
String db = "jdbctutorial";
con = DriverManager.getConnection(url+db, "root", "root");
Statement st = con.createStatement();
String sql = "DELETE FROM employee6 WHERE Emp_code = '1'";
int delete = st.executeUpdate(sql);
if(delete == 1){
System.out.println("Row is deleted.");
System.out.println("Row is not deleted.");
catch (SQLException s){
System.out.println("SQL statement is not executed!");
catch (Exception e){

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