Java Programming with Oracle JDBC

The executeUpdate( ) Method

Now that we’ve created some tables using the execute( ) method, we can continue by using the executeUpdate( ) method to insert, update, and delete rows in those tables. The executeUpdate( ) method works just like the execute( ) method, except that it returns an integer value that reports the number of rows affected by the SQL statement. The executeUpdate( ) method effectively combines the execute( ) and getUpdateCount( ) methods into one call:

int       rslt = 0;
Statement stmt = null;
try {
  stmt = conn.createStatement(  );
  rslt = stmt.executeUpdate("delete person"); 
  . . . 
}

In this example, we once again assume that a Connection object named conn already exists. The example starts by declaring the int variable rslt to hold the number of rows affected by the SQL statement. Next, it declares a Statement variable, stmt, to hold the reference to a Statement object. In the try block, the Statement object is created using the Connection object’s createdStatement( ) method, and a reference to it is stored in stmt. Then, the Statement object’s executeUpdate( ) method is called to execute the SQL DELETE statement, returning the number of rows affected into rslt. Now that you have the general idea, let’s see the executeUpdate( ) method in action.

Executing an INSERT, UPDATE, or DELETE Statement

Example 9-2, shows an insert , update, and delete program which uses the executeUpdate( ) method.

Example 9-2. An application to execute, insert, update, or delete DML

import java.io.*; ...