The point is, that the heap page is only modified in
places that were previously empty (except header).
All previous row data stays exactly in the same place.
Thus if a page is only partly written
(any order of page segments) only a new row is affected.
Exception:
A heap page corruption is not very likely in PostgreSQL because of the
underlying page design. Not even on flakey hardware/ossoftware.
(I once read a page design note from pg 4 but don't exactly remember
were or when)
The point is, that the heap page is only modified in places that were
The point is, that the heap page is only modified in places that were
previously empty (except header). All previous row data stays exactly
in the same place. Thus if a page is only partly written
(any order of page segments) only a new row is affected.
Exception: PageRepairFragmentation()
A heap page corruption is not very likely in PostgreSQL because of the
underlying page design. Not even on flakey hardware/ossoftware.
(I once read a page design note from pg 4 but don't exactly remember
were or when)
The point is, that the heap page is only modified in places that were
