Data is always at the center of any application development, and scaling data has always been challenging. Handling data efficiently improves application latency and performance. In the previous section, Building cache-based architecture, you learned how to handle frequently queried data by putting a cache in front of your database under the app caching pattern. You can put either a Memcached or Redis cache in front of your database, which reduces the many hits on the database and results in improving database latency.
In application deployment, as the user base of your application grows, you need to handle more data with your relational database. You need to add more storage or vertically scale the database server by adding more memory and CPU power. Often, horizontal scaling is not very straightforward when it comes to scaling relational databases. If your application is read-heavy, you can achieve horizontal scaling by creating a read replica...
