JDBC Delete Table

This chapter provides examples of how to use JDBC applications to delete tables. Before executing the following examples, please ensure that you have the following conditions:

• To execute the following example, you can useUsernameAndPasswordReplace with the actual username and password.

• Your MySQL or any database you are using has already been started and is running.

NOTE: This is a serious operation, and you must make a firm decision to continue deleting the table, as all content in the table will be lost.

Necessary steps

To create a new database using a JDBC application, you need to perform the following steps-

• Import package:You are required to include the software package that contains the JDBC classes required for database programming. Typically, using import java.sql.* That is enough.

• Register the JDBC driver: You are required to initialize the driver so that you can open the communication channel with the database.

• Establish connection:Use　DriverManager.getConnection() Method to create a Connection object that represents a physical connection to the database server.

• Execute query: Use an object of the Statement type to construct and submit SQL statements to create a table in the selected database.

• Clean up environment: Explicitly close all database resources is required, rather than relying on JVM's garbage collection.

Example code

Copy and paste the following example into JDBCExample.java, compile and run as follows-

//Step1.Import the 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;
　　　try{
　　　　　　//Step2：Register JDBC driver
　　　　　　Class.forName("com.mysql.jdbc.Driver");
　　　　　　//Step3：Establish connection
　　　　　　System.out.println("Connecting to a selected database...");
　　　　　　conn = DriverManager.getConnection(DB_URL, USER, PASS);
　　　　　　System.out.println("Connected database successfully...");
　　　　　　
　　　　　　//Step4：Execute query
　　　　　　System.out.println("Deleting table in given database...");
　　　　　　stmt = conn.createStatement();
　　　　　　
　　　　　　String sql = "DROP TABLE REGISTRATION";
　
　　　　　　stmt.executeUpdate(sql);
　　　　　　System.out.println("Table deleted in given database...");
　　　catch(SQLException se){
　　　　　　//Handle JDBC error
　　　　　　se.printStackTrace();
　　　catch(Exception e){
　　　　　　//Handle Class.forName error
　　　　　　e.printStackTrace();
　　　}finally{
　　　　　　//Used for closing resources
　　　　　　try{
　　　　　　　　　if(stmt!=null)
　　　　　　　　　　　　conn.close();
　　　　　　catch(SQLException se){
　　　　　　}//　Did nothing
　　　　　　try{
　　　　　　　　　if(conn!=null)
　　　　　　　　　　　　conn.close();
　　　　　　catch(SQLException se){
　　　　　　　　　se.printStackTrace();
　　　　　　}
　　　}//End of try
　　　System.out.println("Goodbye!");
}//End of main
}//End of JDBCExample

Now, let's compile the above example as follows:

C:\>javac JDBCExample.java
C:\>

RuntimeJDBCExampleIt will produce the following result-

C:\>java JDBCExample
Connecting to a selected database...
Connected database successfully...
Deleting table in given database...
Table deleted in given database...
Goodbye!
C:\>