如何从mysql中的两个表中选择两列

I am trying to execute this query but i got error " Undefined index: lname".I want to count row from one column(fname) from table a and select column(lname) from other table b. so please help me.

    $result = mysql_query("SELECT COUNT(fname),lname FROM a,b");
    while ($row = mysql_fetch_array($result))
    {
      echo "<tr><td>";
      echo $row['lname'];
      echo "</td>";
      echo "<td>";
      echo $row['COUNT(fname)'];
      echo "</td></tr>";
    }

如果仍然出现错误，您可以尝试分别获取两者：

$result = mysql_query("SELECT COUNT(fname) FROM a");
while ($row = mysql_fetch_array($result))
  {
    echo "<tr><td>";
    echo $row['COUNT(fname)'];
    echo "</td></tr>";

  }

$result1 = mysql_query("SELECT lname FROM b");
while ($row = mysql_fetch_array($result1))
    {
      echo "<tr><td>";
      echo $row['lname'];
      echo "</td></tr>";
   }