Transactions - Teradata Meta Data Services

Transactions

MDS supports two types of one-phase commit transactions: implicit and explicit.

Implicit transactions – are automatically provided at the MDS API level without any special action by the user. These ensure that the data in the MDS repository remains consistent at an MDS object and relationship level. They are required because many MDS APIs must perform multiple SQL commands, all of which must succeed or fail together to maintain repository consistency.

Explicit transactions – are under the express control of the user application and can be used to group multiple MDS API calls into a single all-or-nothing transaction.

Both types of transactions will be implemented using the ANSI Teradata ODBC session mode and ODBC’s manual commit transaction interface. Using the ANSI session mode instead of Teradata’s native mode will allow MDS’s transaction to be more easily ported to other ANSI- and ODBC-compliant platforms. To facilitate this, MDS will avoid sending Teradata-specific transaction management SQL commands directly to Teradata, and will instead use the ODBC transaction APIs to manage transactions.