PDO lastInsertId in the same query - php

Question

Hello so I have a table named tblcontactlist and have 5 columns (contactID, contactName, contactEmail, contactNumber, hashed_id) and this is my working query
$query = "INSERT INTO tblcontactlist (contactName, contactEmail, contactNumber) VALUES (:cname, :cea, :cnum)";
$stmt = $dbc->prepare($query);
$stmt->bindParam(':cname', $contactName);
$stmt->bindParam(':cea', $emailAdd);
$stmt->bindParam(':cnum', $contactNumber);
$stmt->execute();
$last_id = $dbc->lastInsertId('contactID');
$hashed_id = sha1($last_id);
$query2 = "UPDATE tblcontactlist SET hashed_id=:hid WHERE contactID=:cid";
$stmt2 = $dbc->prepare($query2);
$stmt2->bindParam(':hid', $hashed_id);
$stmt2->bindParam(':cid', $last_id);
$stmt2->execute();
What this basically does is insert a new record then updates the latest inserted record with a hashed id on the hashed_id column. Is there a proper way of doing this? I mean shorter code or better code. Thanks!

Answer 1

lastInsertId presupposes that you have a previous INSERT beforehand, that you don't have. In this case, lastInsertId is the max contactID. So I would perform a query to get and hash the max contactID and then perform one insert query (and no update).
//fetch Max contactID
$res=$dbc->prepare("SELECT MAX(contactID) FROM tblcontactlist");
$res->execute();
$fetchMax=$res->fetch(PDO::FETCH_NUM);
$last_id=$fetchMax[0];
//hash the max contactID
$hashed_id = sha1($last_id);
//for reusability you can create a function with the above code.
And now perform the insert query:
$query = "INSERT INTO tblcontactlist (contactName, contactEmail, contactNumber, hashed_id) VALUES (:cname, :cea, :cnum, :hid)";
$stmt = $dbc->prepare($query);
$stmt->bindParam(':cname', $contactName);
$stmt->bindParam(':cea', $emailAdd);
$stmt->bindParam(':cnum', $contactNumber);
$stmt->bindParam(':hid', $hashed_id);
$stmt->execute();
Is that better for you?