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Q) Develop a JDBC application that deletes all the employees from the db. Make use of pure JDBC approach of connectivity



A)
import java.sql.*;
class EmplyeeRemoval {

       public static void main(String[] args) throws Exception{
              Class.forName("oracle.jdbc.driver.OracleDriver");
              Connection con = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:server","scott","tiger");
              Statement st = con.createStatement();
              int rc = st.executeUpdate("DELETE FROM EMPLOYEE");
              System.out.println(rc+"employees are fired");
              st.close();
              con.close();
       }

}

Explanation:
->in the above program execute operation is a method call that is called by main method. The main method calling the execute Update method on the statement object.
->when the deletion statement is executed the all rows are deleted in the database. But in the DML commands are saved when we executed commit; statement in the oracle prompt but we are not used commit; statement in the java program. Because the connection is opened in the auto connection enabled mode.
->“auto connect enabled mode” the connection is opened so that’s why changes are maid permanently.
->”clear scr” is used to clear the oracle prompt.

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