@charmi thekdi Welcome to Microsoft Q&A forums and thank you for your interest in Azure services.
You have a couple of options here
1) Trigger an external entity like an Azure Function or LogicApp when there is an entry in your Outcome table (table that holds processed/not processed data) and send the email
As you rightly pointed out, you can use Azure Database for PostgreSQL’s Notify functionality for sending a notification event as change feed to the listener channel specified in the database.
We have detailed this in an elaborate blog post along with the source code.
2) Poll the Outcome table on a periodic basis to check if there are any new entries and take appropriate action.
If you don't need real-time processing, you can use a Timer Triggered Azure Function to connect to the database and query the table for new entries periodically (you can adjust the interval as per your business need)
This option is less complex as you will not need the Notify functionality and Event Hub infrastructure.
The code sample for connection and querying an Azure Database for PostgreSQL is here
Please let us know if you have any further questions.
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