举例：
$sql="select id,name from table1";
$result=mysql_query($sql);
while($row=mysql_fetch_array($result)){
echo $row['name'];
}
$sql_two="select id,name from table2 where id=$row['id']";
$result_two=mysql_query($sql_two);
while($row_two=mysql_fetch_array($result_two)){
echo $row_two['name'];
}