Read Replicas and Scaling Reads
Many applications read data far more often than they change it: browsing a catalogue, viewing reports, loading dashboards. When those reads start to strain a single database, read replicas are a proven way to share the load.
This article explains what a replica is and where it does — and does not — help.
What a Replica Is
A read replica is a continuously updated copy of your main database. The original (the primary) handles writes, while one or more replicas handle read-only queries, spreading the work across several machines.
Where Replicas Shine
- Heavy reporting that would otherwise slow live operations.
- High-traffic pages that mostly display data.
- Geographic spread — a replica closer to users reduces latency.
The Catch: Replication Lag
Replicas are updated a fraction behind the primary, so a value just written may take a moment to appear. We send any query that must see the very latest data to the primary, and route the rest to replicas.
If you need a hand with any of this, your Progressive Robot delivery team is ready to help. Raise a ticket from the Support area of your client portal or speak to your account manager and we will guide you through the next steps.