Question

<?php 
  $con= mysql_connect("localhost","root","mysql");
  mysql_select_db("Db_name",$con);

  $res=mysql_query("select *from table_name");

  mysql_close($con);   // closing connection before fetching contents.

  while($r=mysql_fetch_array($res)) {
    echo $r['ename'];
  }

?>

This programs works even if i close the connection before fetching contents from the table.

In order get table contents from the $res connection is not necessary ?

Is$res just a program variable ? If so what kind of data structure it is using(associative array ? )

In oracle we have implicit cursor and explicit cursor. Are there any equivalent things in mysql?

In the above program where cursors come into picture ?

Answer 1

$res in your case is a special type called a “Resource”. Simply put it is a collection of the data returned which the mysql_fetch_* functions operate. As such, it can live beyond the connection. Check the documentation for more details.