Trial And Error With Read-Only Replica Queries

Cody Konior stress tests Availability Group round-robin routing:

I’ve been hearing about round-robin read-only routing ever since SQL 2016 came out but whenever I tried to test if it’s working it never seemed to be. But now I know exactly how it works and there’s a few loopholes where it may not trigger, and they’re not the documented ones you’re thinking of.

To test the limits of it you’re going to need:

  • PowerShell 5.1
  • Pester 4 (Install-Module Pester -Force)
  • DbData (Install-Module DbData -Force)

I’ll explain any of the Pester and DbData bits along the way so don’t worry. They’re minor framework stuff.

There’s some good stuff here around connection pooling, so check it out.

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Niko Neugebauer wants statistics updates on tables running on readable Availability Group secondary nodes: Let’s list the basic known details for the possible solution(for the Enterprise Edition of the Sql Server that is):– We can make the secondary replica readable and read the same data on it. (Not that you should do that by default, […]

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