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Transforming Data

Estuary supports various ways to transform your data, whether you do so before or after loading data to your destination.

Transformations before data load​

ETL data pipelines that transform data before loading it to the destination are useful in cases where you want to:

  • Reduce warehouse costs by filtering out unnecessary data before load
  • Load the same transformed data to multiple different destinations
  • Apply transformations outside the source system before loading data back into the source without the intermediate step of a warehouse

Estuary's derivations support all these use cases. Derivations apply transformations to one or more data collections to create a new derived collection.

Find guides on working with derivations using:

Once you have the basics down, more advanced guides cover specific types of transformations, like joining two collections or flattening an array.

Transformations after data load​

ELT data pipelines that transform data after loading it into a destination are particularly useful when you want to keep a complete record of your data and how it was transformed together in your destination. It can also allow for more flexible ad-hoc queries, since data lands as-is in the destination.

Estuary supports ELT pipelines with: