"Mikheev, Vadim" <vmikheev@SECTORBASE.COM> writes:
> If log record was not really flushed on disk in 3. but on-disk image of
> index block was updated in 4. and system crashed after this then after
> restart recovery you'll have unlawful index tuple pointing to where?
> Who knows! No guarantee that corresponding heap tuple was flushed on
> disk.
This example doesn't seem very convincing. Wouldn't the XLOG entry
describing creation of the heap tuple appear in the log before the one
for the index tuple? Or are you assuming that both these XLOG entries
are lost due to disk drive malfeasance?
regards, tom lane