java06_main.java

TBD: Update GenDefines.txt with a $DESCRIPTION for this example.

import java.sql.*;
 
public class java06_main {
 
/*

 * EXAMPLE - java06 for JDBC

 * When you run this example, two databases are created each with a table.

 * Each table is populated with a few rows and finally the data read with

 * a single query.

 * 

 * Full documentation for RDM is available at http://docs.raima.com/rdm/

 * 

 * For simplicity this example utilizes basic exception handling

 * but good programming practices would dictate that this occur in 

 * a full application.

 */

public static void main(String[] args) throws SQLException {
 
 Connection conn = null;
 Statement stmt = null;
 ResultSet rs = null;


try

 {
 CreateDatabases();


/* Create the connection with a simple connection string */

 conn = DriverManager.getConnection("jdbc:raima:rdm://local");
 conn.setAutoCommit(true);


//CreateDatabases(conn);



/* Open the connection to the database */

 stmt = conn.createStatement();
 stmt.execute("USE java06_1");


/* Insert one row into the table in the first database */

 stmt.executeUpdate("INSERT INTO Table1 VALUES (1, 'database1 1')");
 conn.commit();
 
 stmt.execute("USE java06_2");
/* Insert three rows into the table in the second database */

for (int ii = 1; ii < 4; ii++)
 {
 stmt.executeUpdate("INSERT INTO Table2 VALUES (1, 'database2 " + ii + "')");
 }
 
/* Scan through the data, generating the result */

 rs = stmt.executeQuery("SELECT Table1.str, Table2.str FROM Table1, Table2 WHERE Table1.id = Table2.id"); while (rs.next() != false)
 {
 System.out.println(rs.getString(1) + " -- " + rs.getString(2));
 }
 }
catch (SQLException sqle)
 {
 sqle.printStackTrace();
 }
finally

 {
if(rs != null)
 rs.close();
 
if(stmt != null)
 stmt.close();


if(conn != null)
 conn.close(); 
 }
 }


private static void CreateDatabases()
 {
 Connection conn = null;
try {
 conn = DriverManager.getConnection("jdbc:raima:rdm://local");


/* Create the example databases */

 String query1 = "CREATE TABLE Table1 (id INTEGER PRIMARY KEY, str CHAR(30))";
 String query2 = "CREATE TABLE Table2 (id INTEGER, str CHAR(30))";


/* Drop any existing copies of the database */

 DropDatabase(conn, "java06_1");
 DropDatabase(conn, "java06_2");
 
/* Attempt to create the databases */

 CreateThisDatabase(conn, "java06_1", query1);
 CreateThisDatabase(conn, "java06_2", query2); 
 conn.close();
 } 
catch (SQLException sqle)
 {
 sqle.printStackTrace();
 }
 }


private static void CreateThisDatabase(Connection conn, String dbName, String query)
 {
 Statement stmt = null;
/* Create the specified database. Make sure the database is

 * closed when we are done so other databases can be created

 * after this if necessary. */

try

 {
 stmt = conn.createStatement();
 stmt.execute("CREATE DATABASE " + dbName);
 stmt.execute(query);
 conn.commit();
 }
catch(SQLException sqle)
 {
 sqle.printStackTrace();
 }
 }


private static void DropDatabase(Connection conn, String dbName)
 {
 Statement stmt = null;
/* Attempt to drop this database. If the database does not

 * already exist this will fail and we simply ignore the

 * failure for this sample. */

try

 {
 stmt = conn.createStatement();
 stmt.executeUpdate("DROP DATABASE " + dbName);
 }
catch (SQLException sqle)
 {
 sqle.printStackTrace();
 }
 }
}