$ mysqli->准备使用SQL事务

Question

I am pretty new to SQL Transactions and tried to execute following statement which did unfortunately not work...

$stmt = $mysqli->prepare("

BEGIN;

INSERT INTO groups (group_name, group_desc, user_id_fk) VALUES ("'.$groupName.'","'.$groupDesc.'","'.$user_id.'");

INSERT INTO group_users (group_id_fk, user_id_fk) VALUES (LAST_INSERT_ID(), "'.$username.'");

COMMIT;

") or trigger_error($mysqli->error, E_USER_ERROR);

$stmt->execute();

$stmt->close();

Is this even possible what I am trying here or is it completely wrong?

I appreciate every response, thank you!

Answer 1

You are using prepare() wrong way. There is absolutely no point in using prepare() if you are adding variables directly in the query.

This is how your queries have to be executed:

$mysqli->query("BEGIN");

$sql = "INSERT INTO groups (group_name, group_desc, user_id_fk) VALUES (?,?,?)";
$stmt = $mysqli->prepare($sql);
$stmt->bind_param("ssi",$groupName,$groupDesc,$user_id);
$stmt->execute();

$sql = "INSERT INTO group_users (group_id_fk, user_id_fk) VALUES (LAST_INSERT_ID(), ?)";
$stmt = $mysqli->prepare($sql);
$stmt->bind_param("s",$username);
$stmt->execute();

$mysqli->query("COMMIT");