lastStatement property
If set to true, this statement marks the end of the transaction.
The transaction should be committed or aborted after this statement executes, and attempts to execute any other requests against this transaction (including reads and queries) will be rejected. For DML statements, setting this option may cause some error reporting to be deferred until commit time (e.g. validation of unique constraints). Given this, successful execution of a DML statement should not be assumed until a subsequent Commit call completes successfully.
Optional.
Implementation
core.bool? lastStatement;