在PHP中搜索Oracle表

I've written up a page that tries to search my Oracle database. I can't see where I've gone wrong. I can't get any result to display, despite changing my query to "SELECT * FROM Table WHERE Book_Name="..." (Guaranteed to return a result).

$query = "SELECT * FROM Books WHERE Book_Name = 'My Life'"; 

$dbuser = "username..."; 
$dbpass = "password...";
$db = "SSID"; 
$connect = oci_connect($dbuser, $dbpass, $db); 

if (!$connect)  {
  echo "An error occurred connecting to the database"; 
  exit; 
}

$stmt = oci_parse($connect, $query); 
if(!$stmt)  {
  echo "An error occurred in parsing the sql string.
"; 
  exit; 
}

oci_execute($stmt);

?>

some html...

<?php
while(oci_fetch_array($stmt))  {
   $fg1 = oci_result($stmt,"BOOK_NAME");
   echo ($fg1);

   $fg2 = oci_result($stmt,"AUTHOR");
   echo ($fg2);

   $fg3 = oci_result($stmt,"PRICE");
   echo ($fg3);

   $fg4 = oci_result($stmt,"IMAGE_LOCATION");
   echo ("<br><img src=My Url...".$fg4."><br>");    

}
?>

I've made sure the Oracle table is correct also. Thanks for your help.

Update: It appears anything between the while(oci_fetch_array($stmt)) { part will not execute.