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Drop Data Base

This chapter provides an example on how to drop an existing Database using JDBC application. Before executing the following example, make sure you have the following in place:
  • To execute the following example you need to replace the username and password with your actual user name and password.
  • Your MySQL or whatever database you are using, is up and running.
NOTE: This is a serious operation and you have to make a firm decision before proceeding to delete a database because everything you have in your database would be lost.

Required Steps

The following steps are 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.
  • Deleting a database does not require database name to be in your database URL. Following example would delete STUDENTS database.
  • Execute a query: Requires using an object of type Statement for building and submitting an SQL statement to delete the database.
  • Clean up the environment: Requires explicitly closing all database resources versus relying on the JVM's garbage collection.
Sample Code

Copy and paste the 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/";
// 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("Deleting database...");
stmt = conn.createStatement();
System.out.println("Database deleted successfully...");
}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 the above example as follows:

C:\>javac JDBCExample.java

When you run JDBCExample, it produces the following result:

C:\>java JDBCExample
Connecting to a selected database...
Connected database successfully...
Deleting database...
Database deleted successfully...
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