PHP/MYSQL query failing but no error -

my mysqli query failing error blank. can tell me problem is, or how can output info on error?

heres php code:

// create connection $conn = new mysqli($hostname, $username, $password, $dbname); // check connection if ($conn->connect_error) {     die("connection failed: " . $conn->connect_error); }   if(isset($_post['in_wordarray']))        {            $words = $_post['in_wordarray'];      $sql = "select *, (";      $i = 0;     foreach ($words $value) {          if($i == 0) {             $sql .= "(`words` '%$value%')";         } else {             $sql .= " + (`words` '%$value%')";         }          $i++;     }      $sql .= ") `nummatches` `mytable` having `nummatches` >= 3 order `nummatches` desc";     //echo $sql;     $result = $conn->query($sql);      if ($result === true) {         $text_result_array = array();         if ($result->num_rows > 0) {           while ($row = $result->fetch_assoc()) {               $text_result_array[] = $row;           }         // encode response         echo json_encode($text_result_array);         }     } else {         echo $conn->error;     } } else {     echo "bad input";  } 

and resulting sql query looks this:

select *, ((`words` '%word1%') + (`words` '%word2%') + (`words` '%word3%')) `nummatches` `words`having `nummatches` >= 3 order `nummatches` desc 

sorry i'm not experienced php alone, sure returns boolean?

$result = $conn->query($sql); 

if not can remove if statement?

i wrote answer because sadly can't comment yet.