Use ideas from Incremental View Maintenance to know what has changed about node-reactive-postgres

[mitar]

Also related is InvaliDB.

[Venryx]

I've read (parts of some of) the papers on the InvaliDB solution (eg. http://www.vldb.org/pvldb/vol13/p3032-wingerath.pdf), and so far it's the most complete solution I've seen for the problem so far.

Unfortunately, it is closed-source, so is not directly usable outside of the Baqend service; that said, the papers go into a good amount of detail on the design of the system, so it's still a helpful resource for those attempting to build an equivalent open-source solution.

[mitar]

Attaching the paper describing above code.

QuocVinh2016_Article_SynchronousIncrementalUpdateOf.pdf

Also see:

• ntqvinh/PgMvIncrementalUpdate#4
• ntqvinh/PgMvIncrementalUpdate#3
• ntqvinh/PgMvIncrementalUpdate#2

[ntqvinh]

Dear all,

Unfortunately i don't understand node.js. Anyway i think a MS-notification-service-like service for PostgreSQL will be very useful. If there is similar service, you can implement ASYNchronous programming to dramatically improve the performance of the system. We have naive thing like that for C# here: http://it.ued.udn.vn/chuyen-giao-cong-nghe/498-2015-08-03-17-51-21 (http://it.ued.udn.vn/myprojects/pgNotiServ/postgresql-notification-2014.rar).

[mitar]

Interesting. It really looks like we have similar interests. :-) Yes, node.js is chosen because it is great at asynchronous programming. So I would love to implement something like this in node.

[mitar]

An interesting read is how they do this in Hasura. Some notes:

• They also see this similar to materialized view maintenance.
• They currently re-run queries and do not do do incremental updates (same as this package currently).
• They do not use triggers (like this package can do) but use regular refresh interval.
• They do some additional things to batch queries together. Like merge same query with different parameters (like user ID) together. This package does not do any such optimizations.

So a takeaway could be that if you optimize query ru-running enough, maybe incremental updates are not really necessary?

[mitar]

Some other related projects:

• https://www.graphile.org/postgraphile/live-queries/ (one of many projects using replication stream of changes, this one re-runs queries based on changes detected from replication change stream)
• https://github.com/supabase/realtime (using replication stream of changes to broadcast them to clients)
• https://rxdb.info/query-change-detection.html (uses replication stream of changes but knows how to map that to updates to queries)

[mitar]

Noria is a caching layer where the main design is in fact incremental and efficient updating of materialized views. Very similar to what this issue is about.

[mitar]

event-reduce optimizes repeating queries.