Recipe 20.9 Changing Data Using a ResultSet


Problem

You want to change the data using a ResultSet.

Solution

If you have JDBC 2 and a conforming driver, you can request an updatable ResultSet when you create the statement object. When you're on the row you want to change, use the update( ) methods and end with updateRow( ).

Discussion

You need to create the statement with the attribute ResultSet.CONCUR_UPDATABLE as shown in Example 20-10. Do an SQL SELECT with this statement. When you are on the row (only one row matches this particular query because it is selecting on the primary key), use the appropriate update method for the type of data in the column you want to change, passing in the column name or number and the new value. You can change more than one column in the current row this way. When you're done, call updateRow( ) on the ResultSet. Assuming that you didn't change the autocommit state, the data is committed to the database.

Example 20-10. ResultSetUpdate.java (partial listing)
try {    con = DriverManager.getConnection(url, user, pass);    stmt = con.createStatement(        ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);    rs = stmt.executeQuery("SELECT * FROM Users where nick=\"ian\"");    // Get the resultset ready, update the passwd field, commit    rs.first( );    rs.updateString("password", "unguessable");    rs.updateRow( );    rs.close( );    stmt.close( );    con.close( ); } catch(SQLException ex) {    System.err.println("SQLException: " + ex.getMessage( )); }



Java Cookbook
Java Cookbook, Second Edition
ISBN: 0596007019
EAN: 2147483647
Year: 2003
Pages: 409
Authors: Ian F Darwin

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