R: R: space taken by a row & compressed data

> If you just stuck all the integers into a single integer-array column,
> it would be 1600 bytes wide, which is ... hmm ... not quite wide enough
> to trigger the toast logic. Perhaps it would be worthwhile for you to
> run a custom build with TOAST_TUPLE_THRESHOLD/TOAST_TUPLE_TARGET set
> to half their standard values (see src/include/access/tuptoaster.h).

Could you point me to some docs on this TOAST-mechanism?
I only found http://postgresql.zadnik.org/projects/devel-toast.html
but seems very old.
For instance: what kind of method is used to compress data?

> You'd not need to write any specialized code that way.
Great!

> Note that if you sometimes search on the values of one of the non-index
> columns, this might be a bad idea.

No, this never happens.