Copyright Materialize, Inc. and contributors. All rights reserved.

Use of this software is governed by the Business Source License

included in the LICENSE file at the root of this repository.

As of the Change Date specified in that file, in accordance with

the Business Source License, use of this software will be governed

by the Apache License, Version 2.0.

mzexplore — tools for analyzing query plans

bin/mzexplore can extract plans from environments running Materialize. By running:

mzexplore extract plans ... \
          --explainee-type catalog_item \
          --with arity --with humanized_exprs --with join_impls \
          --format json \
          --stage optimized_plan

you can extract JSON files corresponding to the optimized MIR plan of a catalog item.

This directory contains jq scripts for extracting information from these JSON outputs.

• filters.jq: finds all predicates used in filters and returns a list, sorted by number of occurrences descending

• leftjoins.jq: finds unreduced left joins (particularly shaped unions of antijoins and an inner join)

• defs.jq: utility functions

Note that the ASTs we produce in JSON are quite deeply nested, so you can't use stock jq. As of 2024-03-12, there is a PR open to jq to allow you to specify unbounded depth on the command-line, i.e., --depth 0.

If you have multiple JSON files you'd like to analyze together, you can run:

find ~/mz-support/tmpfs/ -name \*.json |
  xargs jq --slurp --depth 0 -f filters.jq