Functions, in my queries? - Between GROQ and a hard place

With GROQ you can do more than return values; you can compute and transform them from within the query.

GROQ offers a number of Functions that you can experiment with. These will save you from needing to "post-process" data in your front end or API to shape data as desired from within the query.

Here are a few simple examples:

count() all the event documents in the dataset

count(*[_type == "event"])

coalesce() takes any number of arguments and returns the first one that isn't null – use it to return the venue name if defined, otherwise the string "To be confirmed"

*[_type == "event" && eventType == "in-person"]{
  "venue": coalesce(venue->name, "To be confirmed")
}

If you have completed Handling schema changes confidently eventType might now be named format – adjust the query above accordingly.

defined() returns true for values that are not null – query only for event documents that have a headline artist

*[_type == "event" && defined(headline)]

Return an array of unique headline artist names that have upcoming events

array::unique(
  *[
    _type == "event" 
    && date > now() 
    && defined(headline)
  ].headline->name
)

This is just scratching the surface! There are functions for geolocation, weighted search, the delta between documents as they change in GROQ webhooks – and more!

The -> above is resolving a reference. References are a powerful part of Sanity; let's learn how to resolve them in GROQ.

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