The data visualized in Data Lens can be transformed, aggregated, filtered and sorted either server-side or client-side, or both:
- You can prepare the data server-side using the Data Lens REST API query language. This is useful for large datasets where data processing requires more powerful resources, but it requires more calls to the API to fetch the data.
For example, one powerful application of server-side data processing is 'map tiling'. This is a mechanism whereby only the data required by the end-user's current viewport is fetched from the server, thus increasing the efficiency of the app. Conversely, for smaller datasets, loading all the data at once to the client can allow smoother transitions in the visualization, such as during zooming and panning in the viewport.