Exception occurred when PHP queried database data

PHP Error while querying database data
The following error occurred when PHP queried the books table in database books!

Notice:trying to get property of Non-object in D:\wamp\Apache\htdocs\php\results.php on line 33

Fatal Error:call to a member function Fetch_assoc () on a non-object in D:\wamp\Apache\htdocs\php\results.php on line 35


The code is as follows:

PHP Code

              <title>Book-o-rama Catalog Search</title>                
Book-o-rama Catalog Search

  Query ($sql);        $num _result= $result->num_rows;            for ($i =0; $i <= $num _result; $i + +) {$row = $result->fetch_assoc (); echo "
". ($i + 1). "            Title: ";            Echo Htmlspecialchars (stripslashes ($row [' author '));            echo "Author:". Stripslashes ($row->newsauthor);            echo "ISBN:". Stripslashes ($row->NEWSISBN); echo "Price:". Stripslashes ($row->newsprice). "
";    }} $result->free (); $db->colse ();? >

The above problem that tiny prawn can give a solution!

------Solution--------------------

PHP code

 $sql = "SELECT * from Books where". $searchtype. " Like '% '. $searchterm. "        %'";            if ($result = $db->query ($sql)) {$num _result= $result->num_rows;                for ($i =0; $i <= $num _result; $i + +) {$row = $result->fetch_assoc (); echo "
". ( $i + 1). "                Title: ";                Echo Htmlspecialchars (stripslashes ($row [' author '));                echo "Author:". Stripslashes ($row->newsauthor);                echo "ISBN:". Stripslashes ($row->NEWSISBN);            echo "Price:". Stripslashes ($row->newsprice). "
";            }}else{echo "fail.";        Exit } 
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