[Solved] PHP-MySQL error inserting data

Question

You override your variable $a

$a = $_POST['id']; // assign here
$a = $db->prepare($sql);// override here

Try to give a different name

$smt = $db->prepare($sql);
$smt->execute(array(':a'=>$a,':b'=>$b,':c'=>$c,':d'=>$d,':e'=>$e));
header("location: books.php");

Accepted Answer

You override your variable $a

$a = $_POST['id']; // assign here
$a = $db->prepare($sql);// override here

Try to give a different name

$smt = $db->prepare($sql);
$smt->execute(array(':a'=>$a,':b'=>$b,':c'=>$c,':d'=>$d,':e'=>$e));
header("location: books.php");