We support rudimentary filtering on connections
condition argument. Currently this allows you to filter for
specific values (e.g.
username: "Alice" or
category: ARTICLE) but more
advanced filters are being discussed. It's important when implementing
filters to keep performance in mind, for that reason it's likely that version
5 will not expose filters for columns that are not indexed.
One of the PostGraphile community members, Matt Bretl, maintains a filter plugin with many advanced filtering capabilities, located at https://github.com/graphile-contrib/postgraphile-plugin-connection-filter; you might like to check it out.