JDBC - Delete Records Example


This tutorial provides an example on how to delete records from a table using JDBC application. Before executing following example, make sure you have the following in place:

  • To execute the following example you can replace username and password with your actual user name and password.

  • Your MySQL or whatever database you are using is up and running.

Required Steps:

There are following steps required to create a new Database using JDBC application:

  • Import the packages: Requires that you include the packages containing the JDBC classes needed for database programming. Most often, using import java.sql.* will suffice.

  • Register the JDBC driver: Requires that you initialize a driver so you can open a communications channel with the database.

  • Open a connection: Requires using the DriverManager.getConnection() method to create a Connection object, which represents a physical connection with a database server.

  • Execute a query: Requires using an object of type Statement for building and submitting an SQL statement to delete records from a table. This Query makes use of WHERE clause to delete conditional records.

  • Clean up the environment: Requires explicitly closing all database resources versus relying on the JVM's garbage collection.

Sample Code:

Copy and past following example in JDBCExample.java, compile and run as follows:

//STEP 1. Import required packages
import java.sql.*;

public class JDBCExample {
   // JDBC driver name and database URL
   static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";  
   static final String DB_URL = "jdbc:mysql://localhost/STUDENTS";

   //  Database credentials
   static final String USER = "username";
   static final String PASS = "password";
   public static void main(String[] args) {
   Connection conn = null;
   Statement stmt = null;
      //STEP 2: Register JDBC driver

      //STEP 3: Open a connection
      System.out.println("Connecting to a selected database...");
      conn = DriverManager.getConnection(DB_URL, USER, PASS);
      System.out.println("Connected database successfully...");
      //STEP 4: Execute a query
      System.out.println("Creating statement...");
      stmt = conn.createStatement();
      String sql = "DELETE FROM Registration " +
                   "WHERE id = 101";

      // Now you can extract all the records
      // to see the remaining records
      sql = "SELECT id, first, last, age FROM Registration";
      ResultSet rs = stmt.executeQuery(sql);

         //Retrieve by column name
         int id  = rs.getInt("id");
         int age = rs.getInt("age");
         String first = rs.getString("first");
         String last = rs.getString("last");

         //Display values
         System.out.print("ID: " + id);
         System.out.print(", Age: " + age);
         System.out.print(", First: " + first);
         System.out.println(", Last: " + last);
   }catch(SQLException se){
      //Handle errors for JDBC
   }catch(Exception e){
      //Handle errors for Class.forName
      //finally block used to close resources
      }catch(SQLException se){
      }// do nothing
      }catch(SQLException se){
      }//end finally try
   }//end try
}//end main
}//end JDBCExample

Now let us compile above example as follows:

C:\>javac JDBCExample.java

When you run JDBCExample, it produces following result:

C:\>java JDBCExample
Connecting to a selected database...
Connected database successfully...
Creating statement...
ID: 100, Age: 30, First: Zara, Last: Ali
ID: 102, Age: 30, First: Zaid, Last: Khan
ID: 103, Age: 28, First: Sumit, Last: Mittal