The last step is to either commit or roll back the transaction, using SQLTransact().
A transaction is a recoverable unit of work, or a group of SQL statements that can be treated as one atomic operation. This means that all the operations within the group are to be completed (committed) or undone (rolled back), as if they were a single operation.
When using DB2® UDB CLI, transactions are started implicitly with the first access to the database using SQLPrepare(), SQLExecDirect() or SQLGetTypeInfo(). The transaction ends when you use SQLTransact() to either roll back or commit the transaction. This means that any SQL statements processed between these are treated as one unit of work.