hasura/graphql-engine · error · RelationshipError

duplicate relationship field {field_name} from {relationship

Error message

duplicate relationship field {field_name} from {relationship_name} associated with source type {type_name}

What it means

While resolving object-type relationships, two relationships on the same source custom type would generate the same GraphQL relationship field name, causing a duplicate field on the source type.

Source

Thrown at v3/crates/metadata-resolve/src/stages/object_relationships/error.rs:15

use crate::stages::{commands, graphql_config, models};
use crate::types::subgraph::{Qualified, QualifiedTypeReference};
use graphql_types as ast;
use open_dds::{
    arguments::ArgumentName,
    commands::CommandName,
    data_connector::DataConnectorName,
    models::ModelName,
    relationships::RelationshipName,
    types::{CustomTypeName, FieldName},
};

#[derive(Debug, thiserror::Error)]
pub enum RelationshipError {
    #[error(
        "duplicate relationship field {field_name} from {relationship_name} associated with source type {type_name}"
    )]
    DuplicateRelationshipFieldInSourceType {
        field_name: ast::Name,
        type_name: Qualified<CustomTypeName>,
        relationship_name: RelationshipName,
    },

    #[error(
        "unknown target model {model_name:} used in relationship {relationship_name:} on type {type_name:}"
    )]
    UnknownTargetModelUsedInRelationship {
        type_name: Qualified<CustomTypeName>,
        relationship_name: RelationshipName,
        model_name: Qualified<ModelName>,
    },

    #[error(

View on GitHub (pinned to 724551b9ae)

Solutions

1. Rename one relationship's GraphQL field name in the relationship metadata
2. Adjust global naming conventions so the two fields differ
3. Remove the duplicate relationship if it was accidental

// ensure unique relationship field names per source type
let mut seen = HashSet::new();
for rel in &type.relationships {
    assert!(seen.insert(rel.graphql_field_name()), "duplicate relationship field");
}

When it happens

Trigger: Two relationships on one source type whose configured/derived field names collide (e.g. both defaulting to the same field_name).

Common situations: Adding a second relationship without setting a distinct GraphQL field name; naming conventions collapsing distinct relationship names.

Related errors

• the model {model_name} has a duplicate root field in the Gra
• %s: %d %s
• %s: decoding graphql response errors: %w
• %s: %w
• %s: decoding graphql responnse data: %w

AI-assisted analysis of hasura/graphql-engine@724551b9ae (2026-08-28). Data as JSON: /api/errors/9db22108ce1d2af3. Report an issue: GitHub.