How to get all distinct document type names in Sanity dataset?

You can get all unique type names from your dataset using GROQ with a query like this:

array::unique(*[]._type)

This works by:

1. *[] - Fetches all documents
2. ._type - Extracts just the _type field from each document (returns an array of type names)
3. array::unique() - Removes duplicates from the array

This is essentially the GROQ equivalent of SQL's "SELECT DISTINCT". The result will be an array of all unique document type names in your dataset.

Alternative approaches:

If you want more control or additional information, you could also use:

// Get types with document counts
{
  "types": array::unique(*[]._type)
}

Or if you want to see the types in a more structured way with counts:

*[] {
  "type": _type
} | order(type) | {"types": array::unique(@.type)}

You can test these queries in:

• The Vision plugin in your Studio
• The groq.dev playground
• Your project's HTTP API query endpoint

The array::unique() function is specifically designed for this kind of operation and is the most straightforward way to get distinct values in GROQ, similar to SQL's SELECT DISTINCT.