Flexibly Aggregate User Activity with Ecto's select_merge

The article explains the power of PostgreSQL and Ecto in creating flexible database queries. It presents a use case where user activity and redemption limits are tracked in a platform called SwayDM. The author describes how data can be aggregated using traditional queries and highlights inefficiencies in retrieving data. To optimize performance, Ecto's select_merge function is introduced, which allows for combining multiple select statements into a single query. This results in more efficient data retrieval and easier management of the aggregation logic. The article includes code examples showing how to implement redemption limits and evaluate them efficiently. The conclusion emphasizes the practical benefits of using select_merge in real-life scenarios.