The relations of a lambda's chains of extends that aren't windows, each
the chain's last, with its lets put back: what the host types before the
steps are read, as an Extend's new columns are typed by the engine
(CubeQueryReadOptions.relationSchemas)
The relations of a lambda's chains of
extends that aren't windows, each the chain's last, with its lets put back: what the host types before the steps are read, as an Extend's new columns are typed by the engine (CubeQueryReadOptions.relationSchemas)