On Mon, Jul 16, 2018 at 8:02 AM, Christopher Browne <cbbro...@gmail.com> wrote:
> On Sun, Jul 15, 2018, 5:30 AM Anto Aravinth, <anto.aravinth....@gmail.com> > wrote: > >> Hello Everyone, >> >> >> I'm playing around with postgresql with SO datasets. In the process, I >> have dumped 60M questions data onto the postgresql. I'm trying to build a >> notification system on top of this, so that, when a user edits a question, >> I need to show a notification to the user when he/she logs in next time. So >> literally, trying to create the clone of SO (with very minimal feature) >> >> I'm not sure, how to get started with this. Read about NOTIFY: >> https://www.postgresql.org/docs/current/static/sql-notify.html >> >> >> Not sure that fits my use case, thanks for your help in this. >> > > > I do not think that the NOTIFY command implemented in postgreSQL is > terribly likely to be useful for your application. > > That command is useful for distribution of notifications to applications > that are continuously connected to the database, which is not likely true > for web app connections, particularly in view of your comment about > notifying users "when they log in next time." > > Instead, you need a table that captures a log of undelivered notifications > of changes to questions. It should capture useful attributes such as.. > - Who made the change > - Who is to be notified > - The time of the change > - Perhaps the nature of the change, which could be pretty open ended > - A reference to the question, e.g. its ID > - Some lifecycle attribute such as "viewed-on" or "acknowledged-on" > > When a user logs in, it should be easy to query that table, providing the > list of unexamined updates. > > Perhaps entries may be removed as soon as they are viewed, or you may need > a more sophisticated lifecycle so they are only removed after some express > indication that the change has been fully acknowledged. > Thanks that helps a lot.
