> You're essentially asking for a random sample of data that is not
> currently in memory. You're not going to get that without some I/O.
No, that sounds reasonable enough. But do you agree with the statement
that my query will just get slower and slower over time as the number of
posts increases while the part having status = 1 is constant?
(Therefore, as the relevant fraction becomes smaller over time, the
"Filter: status = 1" operation becomes slower.)
