Important information is missing on the schema-customization page

[fgroenendijk]

Preliminary Checks

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Summary

I am using a strapi plugin with complex types like Image and Dynamic zones. Sometimes a field did not have a value on any type and this would crash gatsby with an error.

The error I got was:

ERROR #85923 GRAPHQL.VALIDATION
There was an error in your GraphQL query:
Cannot query field "image" on type "STRAPI_ARTICLE".

To prevent this I wanted to use typedefs, but did not know how to correctly the types.
Until I stumbled upon actions.printTypeDefinitions.
This makes this process a lot easier when some fields are optional but initially not filled in.

The page I searched was: https://www.gatsbyjs.com/docs/reference/graphql-data-layer/schema-customization/

Steps to Resolve this Issue

1. Please add some reference to actions.printTypeDefinitions in that page with an explanation that it can be used to infer types.
2. And that to be able to use this correctly you would have to fill in every field once for the schema to be used in const typedefs.