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Trail: JDBC(TM) Database Access
Lesson: New Features in the JDBC 2.0 API

Code Sample for Inserting a Row

The following code sample is a complete program that should run if you have a JDBC 2.0 Compliant driver that implements scrollable result sets.


Note: Tutorial reader Nedzad Hodzic reported that in this example, you cannot use SELECT * FROM TAB_NAME. You must name the columns; otherwise the ResultSet is not updateable. This is a bug he encountered when using an Oracle 8.1.6 database with Oracle driver OCI8.

Here are some things you might notice about the code:

  1. The ResultSet object uprs is updatable, scrollable, and sensitive to changes made by itself and others. Even though it is TYPE_SCROLL_SENSITIVE , it is possible that the getXXX methods called after the insertions will not retrieve values for the newly-inserted rows. There are methods in the DatabaseMetaData interface that will tell you what is visible and what is detected in the different types of result sets for your driver and DBMS. These methods are discussed in detail in JDBC Database Access with Java, but they are beyond the scope of this tutorial. In this code sample we wanted to demonstrate cursor movement in the same ResultSet object, so after moving to the insert row and inserting two rows, the code moves the cursor back to the result set, going to the position before the first row. This puts the cursor in position to iterate through the entire result set using the method next in a while loop. To be absolutely sure that the getXXX methods include the inserted row values no matter what driver and DBMS is used, you can close the result set and create another one, reusing the same Statement object stmt and again using the query SELECT * FROM COFFEES .
  2. After all the values for a row have been set with updateXXX methods, the code inserts the row into the result set and the database with the method insertRow . Then, still staying on the insert row, it sets the values for another row.
 
import java.sql.*;

public class InsertRows {
    public static void main(String args[]) {
        String url = "jdbc:mySubprotocol:myDataSource";
        Connection con;
        Statement stmt;
    try {
        Class.forName("myDriver.ClassName");
    } catch(java.lang.ClassNotFoundException e) {
        System.err.print("ClassNotFoundException: "); 
        System.err.println(e.getMessage());
    }
    try {
        con = DriverManager.getConnection(url, "myLogin", "myPassword");
        stmt = con.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
                       ResultSet.CONCUR_UPDATABLE);
        ResultSet uprs = stmt.executeQuery("SELECT * FROM COFFEES");
        uprs.moveToInsertRow();
        uprs.updateString("COF_NAME", "Kona");
        uprs.updateInt("SUP_ID", 150);
        uprs.updateFloat("PRICE", 10.99f);
        uprs.updateInt("SALES", 0);
        uprs.updateInt("TOTAL", 0);
        uprs.insertRow();
        uprs.updateString("COF_NAME", "Kona_Decaf");
        uprs.updateInt("SUP_ID", 150);
        uprs.updateFloat("PRICE", 11.99f);
        uprs.updateInt("SALES", 0);
        uprs.updateInt("TOTAL", 0);
        uprs.insertRow();
        uprs.beforeFirst();
        System.out.println("Table COFFEES after insertion:");
        while (uprs.next()) {
            String name = uprs.getString("COF_NAME");
            int id = uprs.getInt("SUP_ID");
            float price = uprs.getFloat("PRICE");
            int sales = uprs.getInt("SALES");
            int total = uprs.getInt("TOTAL");
            System.out.print(name + "   " + id + "   " + price);
            System.out.println("   " + sales + "   " + total);
        }

        uprs.close();
        stmt.close();
        con.close();

    } catch(SQLException ex) {
        System.err.println("SQLException: " + ex.getMessage());
    }
}

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