See here for more details:
http://www.postgresql.org/docs/8.0/static/maintenance.html
In short, you don't need to do a vacuum analyze for each connection--it
is a database-specific or table-specific task, not a
connection-specific one. You can use vacuum analyze when you think
things have changed enough in one or all tables to justify its use.
What justifies enough change is a bit of an open question, although I
think a rough number is if a table changes by about 15%, it then needs
a vacuum analyze. In practice, you can just use cron (see man cron on
a unix-like system) to set up a vacuum for nightly, weekly, or
something like that.
Sean
On May 19, 2005, at 6:20 AM, Surabhi Ahuja wrote:
> Analyze command helps increase performance.
> Suppose i have n connections to the database..and each connection i
> query. So does this mean that i need to do an analyse over each of
> those connections.
>
> Cant analyze be done one time...
> and also please tell if there is any way in postgresql to tell it to
> perform analyze periodically after some time gap.
>
> Thank You
> Surabhi
