[pkalinowski]

> Completely agree. For example, why isn't there functionality to define aliases for complex expressions and then reuse those through a query. Simple query-local SQL functions would be nice too.

What about common table expressions? Or custom defined functions?

    with X as ( select... )

It's widely used for analysis

[jeltz]

CTEs can do that, but it is quite clunky for when you just want to reuse a partial per row computation.