The pipeline syntax as presented is nicer than the status quo, but I'd prefer a syntax that models query execution as a directed graph of operations. Doing so would not only make some of the more complex SQL query constructs much more straightforward to represent:
* Joins can be modelled as a "cross-referencing" operation that consume two (or more) data streams and produce a single data stream
* CTEs can be modelled as producing multiple data streams
* Recursive CTEs can be modelled as cycles in the execution graph
* Joins can be modelled as a "cross-referencing" operation that consume two (or more) data streams and produce a single data stream
* CTEs can be modelled as producing multiple data streams
* Recursive CTEs can be modelled as cycles in the execution graph