Re: No vacuum for insert-only database?

Alvaro Herrera wrote:
>>If I only insert data into a table, never update or delete, then I should
>>never have to vacuum it.  Is that correct?
>
> You still need to vacuum eventually, to avoid transaction Id wraparound
> issues.  But not as often.

Thanks.  Any suggestions for what "not as often" means?  For example, if my database will never contain more than 10
millionrows, is that a problem?  100 million rows?  When does transaction ID wraparound become a problem? 

Craig