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Calculations in Subscriptions
In this lesson, we learn to move our calculations from our components into Reactive Subscriptions. We don't want to store calculated values in the database, because that would de-normalize the data. We learn how calculated subscriptions are a solution to database de-normalization.
Code is available: lispcast/understanding-re-frame
Code for this particular lesson is available at the
031 tag .
You can checkout the code in your local repo with this command:
$CMD git clone https://github.com/lispcast/understanding-re-frame.git $CMD cd understanding-re-frame $CMD git checkout -f 031
Because Subscriptions and Events form an interface that encapsulates the structure of the Database, the question becomes "what structure should the Database have?" In this lesson, we explore a small evolution of the Database, from a single use case to a completely general solution. The pattern we use is called Indexed Entities.