Up until this point, all F# data transformation patterns covered were dealing with in-memory collections. That is, important data crunching use cases, such as querying data, already persisted within the enterprise, and ingesting data from outside of the enterprise have not been considered yet.
This chapter covers these data transformation scenarios and related coding patterns:
Querying the external data. I'll begin with querying the data using F# query expressions. We are going to see how the same transformation patterns we distilled in Chapter 8, Data Crunching - Data Transformation Patterns, in relation to core library function members are fully applicable to querying the external data presented in a data base or a web service. It also would be interesting to push the limits of composition in query expressions.
Parsing data from the external sources. We already spent a fair amount of time considering pattern matching amplified by active patterns. However, I...