Andres Freund wrote: > This is implemented using a new infrastructure called "speculative > insertion". It is an optimistic variant of regular insertion that first > does a pre-check for existing tuples and then attempts an insert. If a > violating tuple was inserted concurrently, the speculatively inserted > tuple is deleted and a new attempt is made. If the pre-check finds a > matching tuple the alternative DO NOTHING or DO UPDATE action is taken. > If the insertion succeeds without detecting a conflict, the tuple is > deemed inserted.
Is there a reason why heap_finish_speculative and heap_abort_speculative were made to take a HeapTuple rather than just an ItemPointer? They only use tuple->t_self in their code (except the former, which in an assert verifies that the tuple is indeed speculative). -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers