include-attributes-when-conditional-check-passes.md

Include Attributes When Conditional Check Passes

The graph-like nature of Sanity means that you'll often be querying for data that spans a variety of document types. For instance, your front-end could be requesting content in the shape of a blog post, video, and podcast. Though there are some similarities, each of these document types will have some unique attributes.

When using GROQ to query for data that spans different types of documents, you can use a conditional query syntax to include type-specific attributes.

*[_type == 'blog' || _type == 'video' || _type == 'podcast'][]{
  title,
  'slug': slug.current,
  _type == 'blog' => {
    body,
    read_time
  },
  _type == 'video' => {
    description,
    mp4_url
  },
  _type == 'podcast' => {
    description,
    mp3_url
  }
}

Notice that there are some attributes that are common across each type (i.e. title and slug). Each type then has attributes unique to its document type (i.e. blog has body and read_time).

This conditional query syntax allows us to both define flexible schemas in Sanity and then query against that flexible schema.

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