@vlcn.io/rx-query v0.8.0

@vlcn.io/rx-query

WIP - more efficient query based reactivity.

rx-tbl would re-run all queries that hit a given table when a write hit that table. This is problematic for apps with hundreds of queries against the same table.

Why would this happen? Well imagine a presentation editor. You have little slide thumbnails or previews. Each of these previews would query a component table to get the components belonging to the slide. Any time you add a component on a slide, each preview would re-query the component table. If you have hundreds of slides this could be hundreds of queries with the dumb rx-tbl approach.

rx-query looks at the write being made and finds the exact queries that would be impacted by that write.

Where this is efficient

• Single table queries (SELECT * FROM foo WHERE ...)
• Queries that do a single hop join (SELECT * FROM foo JOIN bar ON foo.id = bar.foo_id WHERE ...)
• Updates that include WHERE conditions on the same columns used by select queries
• Deletes that include WHERE conditions on the same columns used by select queries
• Inserts

Where this is inefficient

• Queries that do multi-hop joins (SELECT foo.* FROM foo JOIN bar ON foo.id = bar.foo_id JOIN baz on bar.baz_id = baz.id)
• Updates or deletes that do not include WHERE conditions on the same columns used by select queries
• When thousands of queries against the same table are active. We currently scan the list of active queries for a table on insert. This is fine up to a few hundred active queries against a single table. In the future we'll introduce range trees to optimize this case.