[Known Issue]: Autoentities fail when table names generate duplicate GraphQL operations

[JerryNixon]

When autoentities includes objects such as dbo.Category and dbo.Categories, DAB automatically derives entity and GraphQL names from each database object.

During this process, DAB applies singularization and pluralization rules. Both object names can therefore resolve to the same GraphQL type and operation names:

Singular: Category
Plural: Categories

This causes the generated queries and mutations for one entity to conflict with those already generated for the other entity. DAB detects the duplicate names during runtime initialization and stops the application.

The current error states that the entity generates queries or mutations that already exist, but it does not identify:

• The other conflicting entity
• The generated GraphQL names
• The specific queries or mutations that conflict
• How the developer can resolve the conflict

Problem

DAB should return a clearer error that includes these details. For example:

GraphQL naming conflict detected.

Entities:
  dbo.Category
  dbo.Categories

Both entities generate the following GraphQL names:
  Singular type: Category
  Plural type: Categories

Configure distinct GraphQL singular and plural names for one of the entities.

When

The following autoentities configuration includes two tables whose names differ only by singular and plural form:

"autoentities": {
  "default": {
    "patterns": {
      "include": [
        "dbo.Category",
        "dbo.Categories"
      ]
    }
  }
}

And when

The database contains both tables:

Then

DAB fails during runtime initialization:

fail: Azure.DataApiBuilder.Service.Startup[0]
      Unable to complete runtime initialization. Refer to exception for error details.
      Azure.DataApiBuilder.Service.Exceptions.DataApiBuilderException: Entity dbo_Category generates queries/mutation that already exist
         at Azure.DataApiBuilder.Core.Configurations.RuntimeConfigValidator.HandleOrRecordException(Exception ex) in /_/src/Core/Configurations/RuntimeConfigValidator.cs:line 1675
         at Azure.DataApiBuilder.Core.Configurations.RuntimeConfigValidator.ValidateEntitiesDoNotGenerateDuplicateQueriesOrMutation(DatabaseType databaseType, RuntimeEntities entityCollection) in /_/src/Core/Configurations/RuntimeConfigValidator.cs:line 805
         at Azure.DataApiBuilder.Core.Configurations.RuntimeConfigValidator.ValidateEntityAndAutoentityConfigurations(RuntimeConfig runtimeConfig) in /_/src/Core/Configurations/RuntimeConfigValidator.cs:line 1769
         at Azure.DataApiBuilder.Core.Services.SqlMetadataProvider`3.InitializeAsync() in /_/src/Core/Services/MetadataProviders/SqlMetadataProvider.cs:line 346
         at Azure.DataApiBuilder.Core.Services.MetadataProviders.MetadataProviderFactory.InitializeAsync() in /_/src/Core/Services/MetadataProviders/MetadataProviderFactory.cs:line 95
         at Azure.DataApiBuilder.Service.Startup.PerformOnConfigChangeAsync(IApplicationBuilder app) in /_/src/Service/Startup.cs:line 1301

Expected behavior

DAB should continue to reject duplicate GraphQL names because allowing the conflict would create an ambiguous API schema.

However, the error should identify both entities and the generated names that conflict. It should also explain that the developer must assign distinct GraphQL singular and plural names.

Workaround

Exclude one or both conflicting tables from autoentities, then configure them explicitly under entities.

Explicit entity configuration allows the developer to assign GraphQL names that do not conflict with names generated for other entities.

For example, dbo.Category can retain the generated Category and Categories names while dbo.Categories uses CategoryCollection and CategoryCollections.

Entity example

"entities": {
  "dbo_Categories": {
    "source": {
      "object": "dbo.Categories",
      "type": "table"
    },
    "graphql": {
      "type": {
        "singular": "CategoryCollection",
        "plural": "CategoryCollections"
      }
    },
    "permissions": [
      {
        "role": "anonymous",
        "actions": [
          "*"
        ]
      }
    ]
  }
}

This produces distinct GraphQL names for the two entities and prevents the generated queries and mutations from colliding.