SQL + Java

scojones

Here's the code to my program:
<start>
import java.io.*;
import java.net.*;
import java.sql.*;
import java.util.*;

public class feh {

private static BufferedReader input = new BufferedReader
(new InputStreamReader(System.in));


public static void main(String argv[]) throws Exception {


Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");

String url = "jdbc:odbc:oracle";
String username, password, sqlQuery;

System.out.print("\nEnter username: ");
username = input.readLine();
System.out.print("\nEnter Password: ");
password = input.readLine();
System.out.print("\nEnter SQL Query: ");
sqlQuery = input.readLine();
Connection con = DriverManager.getConnection(url, username, password);

Statement stmt = con.createStatement();

ResultSet rs = stmt.executeQuery(sqlQuery);

while (rs.next()) {
String s1 = rs.getString(1);
String s2 = rs.getString(2);
System.out.println(s1 + "\t" + s2);

}
con.close();
System.out.print("\nClosed connection");
}//end of main()
}//end of feh
<stop>

Right, if my sql query is "SELECT * FROM Emp;" the while statement will print the first two columns of the table Emp back to me. That's fine i understand that. But i was wondering is there a way to print the entire results gotten from "SELECT * FROM Emp;", every column for each row in the table Emp. I will supply Emp if needs be.

Karoma

not quite sure what you're asking. My understanding is that you don't want to 'hard-type' how many results will be returned /dealt with (!?). (A) solution: Polymorphic variable + array. (See java.sun.com / google.ie).

or a simpler approach:

while (rs.next()) {
String s1 = rs.getString(1);
String s2 = rs.getString(2);
System.out.println(s1 + "\t" + s2);

}


to:

int i = 0;

while (rs.next()) {
i++; // increment i -- loop!
String s1 = rs.getString(i); // 'put' result into s1...
printMethod(s1); // pass the result to another method(below)


// this method will take the result passed...
public void printMethod(String passedString)
{
//...and print it (+ a tab)
System.out.println(passedString+ "\t");
}


ok. me tired. lemme know if it's in the right direction at all....

Korg

Could be wrong but sounds like ResultSetMetaData is what you're after, this object can be retrieved from a ResultSet object & contains things like the names of all the columns returned etc:

http://java.sun.com/j2se/1.4.1/docs/api/java/sql/ResultSetMetaData.html

I've no compiler to hand so i could be typing crap (should work tho) but you get the general idea.

[PHP]

ResultSet rs = stmt.executeQuery( "SELECT * FROM Emp" );
ResultSetMetaData rsmd = rs.getMetaData();

for( int nRow = 0; rs.next(); nRow++ )
{
System.out.println( "Row: " + nRow );

for( int nColumn = 1; nColumn <= rsmd.getColumnCount(); nColumn++ )
{
String sColumnName = rsmd.getColumnName( nColumn );
String sColumnValue = rs.getString( sColumnName );

System.out.println( '\t' + sColumnName + ": " + sColumnValue );
}
}


[/PHP]

scojones

Thanks to the both of you for your quick replys. Korg I'm going with yours as I didn't know ResultSetMetaData even existed, and the output is very nice. Many thanks friends.