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Comment by porsager | Hacker News Reader

You could use a column/table to track notifications. Eg. have an alert_sent_at column on the alerts table. Then when the node service receives the notify on an insert you can defer based on any logic you need, and send notifications when needed by a query that fetches alerts with alert_sent_at = null.

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Thank you! Thank you so much :)

You're welcome. To ensure you're not sending alerts twice either select and update in a transaction or use a CTE like:

  with alert as (
    select alert_id from alerts 
    where alert_sent_at is null
  )
  
  update alerts set
    alert_sent_at = now()
  from alert
  returning *

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