Makes sense. I appreciate your thorough question, and I completely agree that we should point out this expression-substitution behavior in the performance guide. It's not the first time it has come, and I'd imagine it will not be the last 🙂 Btw, if you really really want to get the materialization behavior with an inline view without an ORDER BY, then you can apply the following terrible hack. Original query: select a, b, c from (select f(x) as a, f(y) as b, f(z) as c from mytable) v Modified query to force materialization of inline view: select a, b, c from (select f(x) as a, f(y) as b, f(z) as c from mytable union all select NULL, NULL, NULL from mytable where false) v The "union all" will force materialization, but the second union operand will be dropped due to the "false" predicate. Obviously, that behavior is implementation defined and subject to change any time, so it would be wise not to rely on it.
... View more
