//************************************************************************************
//
// Copyright (c) 2004-2008 by Teradata Corporation
// All Rights Reserved
//
// TERADATA CORPORATION CONFIDENTIAL AND TRADE SECRET
//
//************************************************************************************
//
// File: T20100JD.java
// Header: none
// Purpose: Demonstrate the JDBC API for retrieving statement
// result set meta data.
// The program will:
// - Connect as user guest/please
// - Prepare an SQL statement
// - Obtain result set meta data
// - Disconnect.
//
// JDBC API: java.sql.Connection,
// java.sql.Statement, java.sql.Statement.executeQuery,
// java.sql.ResultSet, java.sql.ResultSet.getMetaData,
// java.sql.ResultSetMetaData
//
// Version: Updated for Teradata V2R6
//
//************************************************************************************
import java.sql.*;
public class T20100JD
{
// Name of the user able to create, drop, and manipulate tables
public static String sUser = "guest";
public static String sPassword = "please";
public static void main(String args[])
throws ClassNotFoundException
{
// Creation of URL to be passed to the JDBC driver
String url = "jdbc:teradata://whomooz/TMODE=ANSI,CHARSET=UTF8";
// Query statement selecting all columns of the table. Using this query,
// result set column metadata can be retrieved.
String sSelAll = " SELECT * FROM employee";
try
{
System.out.println(" Sample T20100JD: ");
System.out.println(" Looking for the Teradata JDBC driver... ");
// Loading the Teradata JDBC driver
Class.forName("com.teradata.jdbc.TeraDriver");
System.out.println(" JDBC driver loaded. ");
// Attempting to connect to Teradata
System.out.println(" Attempting to connect to Teradata via" +
" the JDBC driver...");
// Creating a connection object
Connection con = DriverManager.getConnection(url, sUser, sPassword);
System.out.println(" User " + sUser + " connected.");
System.out.println(" Connection to Teradata established. ");
try
{
// Creating a statement object from an active connection
Statement stmt = con.createStatement();
System.out.println(" Statement object created. ");
try
{
// Performing the SELECT query using Statement.executeQuery
// method. This method executes a SQL statement that returns
// a single ResultSet. Only one ResultSet per Statement can
// be open at any point in time. If the reading of one
// ResultSet is interleaved with the reading of another,
// each must have been generated by different Statements.
// A ResultSet provides access to a table of data generated
// by executing a Statement. The table rows are retrieved
// in sequence. Within a row, its column values can be
// accessed in any order.
ResultSet rset = stmt.executeQuery(sSelAll);
// Retrieve the properties of the ResultSet object.
// A ResultSetMetaData object can be used to determine
// the types and properties of the columns in a ResultSet.
ResultSetMetaData rsmd = rset.getMetaData();
// Retrieve the number of columns returned
int colCount = rsmd.getColumnCount();
System.out.println(" This table has " + colCount + " columns.");
// For every column, display it's information.
System.out.println(" Displaying column information: ");
int i = 1; // Initialize loop counter
while(i <= colCount)
{
// This code will demonstrate all available methods for
// retrieving column meta data.
System.out.println();
System.out.println(" Column " + i);
System.out.println(" ------------ ");
// Display the suggested column title for use in
// printouts and displays
System.out.println(" Column label: "
+ rsmd.getColumnLabel(i));
// Display the column name
System.out.println(" Column name: "
+ rsmd.getColumnName(i));
// Display the SQL type of a column.
System.out.println(" Column type: "
+ rsmd.getColumnType(i));
// Display the type name of a column
System.out.println(" Column type name: "
+ rsmd.getColumnTypeName(i));
// Display the class name of a column - DR89445
System.out.println(" Column class name: "
+ rsmd.getColumnClassName(i));
// Display information on whether NULL values are allowed
System.out.println(" NULLs allowed: "
+ rsmd.isNullable(i));
// Display the normal maximum width of a column in characters.
System.out.println(" Maximum character width: "
+ rsmd.getColumnDisplaySize(i));
// Display precision: the number of decimal digits
// Note: default value is 0.
System.out.println(" Column precision"
+ " (number of decimal places): "
+ rsmd.getPrecision(i));
// Display the number of digits to the right of the
// decimal point. Note: default value is 0.
System.out.println(" Precision to the right of"
+ " the decimal point: "
+ rsmd.getScale(i));
// Increment column counter
i++;
}
}
finally
{
// Close the statement
stmt.close();
System.out.println(" Statement object closed. ");
}
}
finally
{
// Close the connection
System.out.println(" Closing connection to Teradata...");
con.close();
System.out.println(" Connection to Teradata closed. ");
}
System.out.println(" Sample T20100JD finished. ");
}
catch (SQLException ex)
{
// A SQLException was generated. Catch it and display
// the error information. Note that there could be multiple
// error objects chained together.
System.out.println();
System.out.println("*** SQLException caught ***");
while (ex != null)
{
System.out.println(" Error code: " + ex.getErrorCode());
System.out.println(" SQL State: " + ex.getSQLState());
System.out.println(" Message: " + ex.getMessage());
ex.printStackTrace();
System.out.println();
ex = ex.getNextException();
}
throw new IllegalStateException ("Sample failed.") ;
}
} // End main
} // End class T20100JD
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