Whether you have come here intentionally (which would be quite surprising), or completely by mistake and have decided to read on, I have to warn you that once in a while, my cheerful amigo there mich, will produce an unlimited amount of uncomprehensible psychobabble which sounds something like this::
"The `vacuum` command (or the vacuumdb shell script) will garbage collect your db.
If you run it together with the analyzer option, it will calculate statistics for use by the
optimizer... As an example, I just gained a factor 30 of increased query speed on a table
in one of my databases"
This is due to a condition which has surfaced in the last couple of years, closely associated with Turret's syndrome and manic depressive confinement. It is not dangerous at first, but is utterly USELESS to most people who have enough neurons to make that whole 'hand-eye coordination' thing work.
I suggest that when you see this gagababble, simply run to the next paragraph, basically, to what I have to say. (unless of course mich has a moment of lucidity and writes anything about jugs, sex, beer, dumps, blogs, ghettos and hoes.
You've been warned