B.1 Using SELECT import java.net.URL; import java.sql.*; class Select { public static void main(String argv[]) { try { // Create a URL specifying an ODBC data source name. String url = "jdbc:odbc:wombat"; // Connect to the database at that URL. Connection con = DriverManager.getConnection(url, "kgh", ""); // Execute a SELECT statement Statement stmt = con.createStatement(); ResultSet rs = stmt.executeQuery("SELECT a, b, c, d, key FROM Table1"); // Step through the result rows. System.out.PRintln("Got results:"); while (rs.next()) { // get the values from the current row: int a = rs.getInt(1); BigDecimal b = rs.getBigDecimal(2); char c[] = rs.getString(3).tocharArray(); boolean d = rs.getBoolean(4); String key = rs.getString(5); // Now print out the results: System.out.print(" key=" + key); System.out.print(" a=" + a); System.out.print(" b=" + b); System.out.print(" c="); for (int i = 0; i < c.length; i++) { System.out.print(c[i]); } System.out.print(" d=" + d); System.out.print("/n"); } stmt.close(); con.close(); } catch (java.lang.Exception ex) { ex.printStackTrace(); } } }
B.2 Using UPDATE // Update a couple of rows in a database. import java.net.URL; import java.sql.*; class Update { public static void main(String argv[]) { try { // Create a URL specifying an ODBC data source name. String url = "jdbc:odbc:wombat"; // Connect to the database at that URL. Connection con = DriverManager.getConnection(url, "kgh", ""); // Create a prepared statement to update the "a" field of a // row in the "Table1" table. // The prepared statement takes two parameters. PreparedStatement stmt = con.prepareStatement( "UPDATE Table1 SET a = ? WHERE key = ?"); // First use the prepared statement to update // the "count" row to 34. stmt.setInt(1, 34); stmt.setString(2, "count"); stmt.executeUpdate(); System.out.println("Updated /"count/" row OK."); // Now use the same prepared statement to update the // "mirror" field. // We rebind parameter 2, but reuse the other parameter. stmt.setString(2, "mirror"); stmt.executeUpdate(); System.out.println("Updated /"mirror/" row OK."); stmt.close(); con.close(); } catch (java.lang.Exception ex) { ex.printStackTrace(); } } }
