$res = select * from table1 where column1 = 'value';
mysql_query("Update table2 set col2 = '$res[`1`]' ");

$res = mysql_query("select * from table1 where column1='value'"); 
while($row = mysql_fetch_array($res)) {
$value2 = $row['column2']; //assign column2 value to $value2
$query = mysql_query("update table2 set col2='$value2'"); //update col2 in table2
}
?>

// retreiving data from table 1
 
$r1 = mysql_query("Select * from table1 where Column1 = '$test' ") or die(mysql_error()); 
 
 
//  updating the other table
 
while($row = mysql_fetch_array($r1))
{
	$value2 = $row['Rate'];
 
	$query  = mysql_query("update table2 set amt = '$value2' ");
}