How it's working ? Well, quite manually: transactions are explicitely started when needed ($db->begin()), and ended after the transaction unsafe queries have been executed, using $db->commit(). If an error occurs on any of those queries, the transaction is automatically rollbacked.
And what I mean with non-atomic operations is... well, what it means: operations which aren't meant to be part of a transaction because they're not critically dependent on each other ?
I've seen these code lines (and use them ;) ), but I'm searching how it's working exactly with the db handler.
I've checked in lib/ezdb/classes/ezmysqlidb.php, found the query( "COMMIT" ).... but nothing to allow this COMMIT with transactions (using the set autocommit=0; stuff ).
That's the thing disturbing me.
Sorry to bug you about, and apologize for my english. Just want to learn. ;)
No problem whatsoever with your english, Laurent. Most of us here don't speak english as their native language anyway :)
Regarding the set autocommit part, it is a bit unrelated: we indeed don't disable autocommit, because, well, there is no need to. When a query isn't considered transaction unsafe (e.g. it can be executed independantly from the previous one), we just execute the query. Now if a set of queries are interdependant on each other, we do explicitely start a transaction ($db->begin()), and as the manual says (http://dev.mysql.com/doc/refman/5.0/en/commit.html), starting a transaction will disable autocommit.
We then just execute the "transaction unsafe" queries, and commit them using $db->commit(). If an error occurs in the transaction, the query is automatically rollbacked by the DB layer. Does it make sense ?