javascript - notification to the user when a table in the database change -

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i'm using spring project , need best solution problem, because affect performance system. better using javascript or create method on java ?

from web server:

  1. poll database, , check new data
  2. or listen notifications database. preferred method. you'd need postgresql or oracle though

from web browser:

  1. reload page using refresh header (don't this)
  2. poll server using ajax
  3. use comet
  4. use server-sent events. lightest weight.
  5. use websocket

here's how spring, postgresql, , websocket: http://blog.databasepatterns.com/2014/04/postgresql-nofify-websocket-spring-mvc.html


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