Re:

Andrew Bell <acbell@iastate.edu> writes:
> Can anybody tell me what this means, or where to look in the docs to find
> out more?

> ERROR:  cache lookup of attribute 0 in relation 318304 failed

Looks like a bug of some kind to me: that's a low level routine
complaining that it didn't find an entry in pg_attribute, which indeed
it wouldn't find for attribute zero (we number attributes from 1).
So some other bit of code is passing in a bogus attribute number.
May we see a reproducible example?

            regards, tom lane