Rolls back all outstanding statements for the Oracle
TRUE on success or
FALSE on failure.
Transactions are automatically rolled back when you close
the connection, or when the script ends, whichever is soonest. You
need to explicitly call oci_commit() to commit
the transaction, or oci_rollback() to abort it.
In PHP versions before 5.0.0 you must use ocirollback() instead.
This name still can be used, it was left as alias of
oci_rollback() for downwards compatability.
This, however, is deprecated and not recommended.