mySQL Transaction Rollback

I'm new to PHP & mySQL, and currently I'm working on a function which does the following: connect to db, insert into 3 different tables, close the connection. Here's the code:

$db = mysql_connect("localhost", "root", "pwd") or die("Could not connect: ".mysql_error());
mysql_select_db("HR", $db);
$query = "INSERT INTO tblA (Field1, Field2) values ('a', 'b');
$sql = mysql_query($query) or die("Query Error: ".mysql_error());
$IndexNo = mysql_insert_id();

$query2 = "INSERT INTO tblB (Index, Field) values ($IndexNo, 'b');
$sql = mysql_query($query2) or die("Query Error: ".mysql_error());

$query3 = "INSERT INTO tblC (Index, Field) values ($IndexNo, 'b');
$sql = mysql_query($query3) or die("Query Error: ".mysql_error());

mysql_close($db);

Now, I don't want it to autocommit. So in case there's error while inserting tblC, the insert statement for tblA and tblB will be cancelled. I know I have to use start transaction and rollback if there's an error. But I'm not sure about the coding. Can anyone help?

Thanks a lot!

MySQL is set to autocommit by default...

Try using SET AUTOCOMMIT=0 to disable autocommiting

Also realize, you must use a recent MySQL version which supports InnoDB tables

Notice that when doing that you need to *always* use commit to save changes...

To change it so you only autocommit in a transaction, try this:



PHP *does* support transactions, use seperate query statements for each command...



hopefully this helps a bit?

MySQL documentation:
http://www.mysql.com/doc/en/COMMIT.html

MySQL's growing up: Transactions [web monkey]:
http://hotwired.lycos.com/webmonkey...dex3a_meta.html