Sean Chen <zyschen@gmail.com> wrote:
> 1, delete records ...
> 2, insert records ...
>
> if I add "vacuum analyze" in-between this two steps, will it help
> on the performance on the insert?
Assuming there are no long-running transactions which would still be
able to see the deleted rows, a VACUUM between those statements
would allow the INSERT to re-use the space previously occupied by
the deleted rows, rather than possibly needing to allocate new space
from the OS.
-Kevin