Teradata mode transactions can be implicit or explicit. An explicit, or user-generated, transaction is one or more requests surrounded by BEGIN TRANSACTION and END TRANSACTION statements. Other requests are implicit transactions.
Consider the following transaction:
BEGIN TRANSACTION; DELETE FROM Employee WHERE Name = 'Smith T'; UPDATE Department SET EmpCount=EmpCount-1 WHERE DeptNo=500; END TRANSACTION;
If an error occurs while processing the DELETE or UPDATE statement, the system restores both the Employee and Department tables to their pre-transaction states. If an error occurs during a Teradata transaction, the system rolls back the transaction.