SELECT SUM not working in php code. How do I use it with mysqli -


the name of table "hit" , name of row sum of "amount" code not working

 <?php          $result = $mysqli->query('select sum(amount) hits');         if (false === $result) die("select sum failed: ".mysqli_error);         $row = mysqli_fetch_row($result);         $sum = $row[0];         print $sum;           ?>

the error "notice: use of undefined constant mysqli_error - assumed 'mysqli_error' in ..."

there no such mysqli_error() method available in php till now. there mysql_error() shouln't confuse it.

the solution

if (false === $result) die("select sum failed: " . $mysqli->error);

more mysqli error


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