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Version: Draft

Naming conflict

You're probably here because you just received an error like:

Error: A naming conflict has occurred - two entities have tried to define the same key 'task'.
  The first entity was:
    Adding 'task' attribute field to GraphQL type 'Subtask' (representing PgCodec 'subtask')
  The second entity was:
    Adding field to GraphQL type 'Subtask' for singular relation 'taskByMyTask'
  Details: https://err.red/pnc

This happens when PostGraphile tries to add an entry to an object, where that object already has an entry with that name. There is a very large number of circumstances under which this can happen since the build.extend method is used to avoid conflicts throughout the PostGraphile schema building process: when creating codecs, resources or relations; when adding attributes; when defining GraphQL fields, arguments or enum values; and much more.

Fortunately we try and give you more details about how the error has come about by detailing the key ('task' above) that has conflicted, and where the first and second conflicting entities originated from.

When reading about the entities, you should keep in mind that codec/PgCodec, resource/PgResource, and relation/PgCodecRelation relate to the concepts described in the registry documentation.

A common situation where this would occur is where you have two different things (e.g. a column and a relationship) that are trying to be assigned to the same field name in the GraphQL schema. This is particularly common when using @graphile/simplify-inflection because it deliberately shortens the names of relations for better ergonomics (e.g. userByAuthorId might become simply author), at the risk of causing more conflicts - this is the main reason this preset isn't enabled by default.

Another common situation is where you have two things of the same type (e.g. two columns) whose names are made the same after inflection (e.g. columns named thing_2name, thing2_name, thing2name and thing2Name would all transform to a GraphQL field called thing2Name in the default inflectors).

To resolve the issue, you should either:

  1. use a smart tag to assign a different name or field name to one or both of the entities, or
  2. use a custom inflector to change the way the names are generated for the entities, or
  3. do something else suitable for the situation.

If you really are not sure what to do, please come ask us in the #help-and-support channel on our Discord at https://discord.gg/graphile - we might even add the solution to this page for future users!