Queries in Beta Malloy

[mtoy-googly-moogly]

The Problem

DO NOT COMMENT YET -- I am beginning to write this up, I will post to the malloy channel when it is ready for review.

This spun out of #29 into its own discussion.

At the. most general, we need to parse (roughly) these sentences ...

exploreRef: exploreName exploreRefinements exploreParameters
queryRef: queryName queryRefinements queryParameters
query: exploreRef queryRef

We already know in beta-malloy that refinements look like { propertyList }.

The Solutions

Arrow Proposal

This is the proposal currently in beta-Malloy. There are a number of objections to this which suggest other solutions.

• There is an operator -> which takes an explore def on the left hand side and a query def on the right hand side ...

  -- run a query
  flights->by_carrier
  -- refine the explore, and refine the query
  flights { refine for flights } -> by_carrier { refine for by_carrier }
  -- define a new explore based on query
  explore: refine_by_carrier is (flights->by_carrier) { primary_key: carrier_name }

Dot / Paren Proposal

exploreName { exploreRefine } ( exploreParamValues ) . queryName { queryRefine } ( queryParamValues )

• The () is optional on an explore which has no parameters
• the () is NOT optional on a query which has no parameters

[mtoy-googly-moogly]

no longer discussing, 4.0 is the end of this train