hasura/graphql-engine · error · NDCValidationError

column {column_name} is not defined in collection {collectio

Error message

column {column_name} is not defined in collection {collection_name} in data connector {db_name}

What it means

NDCValidationError::NoSuchColumn is thrown when a field on a model maps to a column (DataConnectorColumnName) that the connector's schema does not define for the mapped collection. During NDC validation each mapped field's column is looked up in the collection's columns; a miss raises this with db_name, model_name, field_name, collection_name, and column_name.

Source

Thrown at v3/crates/metadata-resolve/src/helpers/ndc_validation.rs:43

        collection_name: CollectionName,
    },
    #[error(
        "argument {argument_name} is not defined for collection {collection_name} in data connector {db_name}"
    )]
    NoSuchArgument {
        db_name: Qualified<DataConnectorName>,
        collection_name: CollectionName,
        argument_name: DataConnectorArgumentName,
    },
    #[error(
        "argument {argument_name} is not defined for function/procedure {func_proc_name} in data connector {db_name}"
    )]
    NoSuchArgumentForCommand {
        db_name: Qualified<DataConnectorName>,
        func_proc_name: String,
        argument_name: DataConnectorArgumentName,
    },
    #[error(
        "column {column_name} is not defined in collection {collection_name} in data connector {db_name}"
    )]
    NoSuchColumn {
        db_name: Qualified<DataConnectorName>,
        model_name: Qualified<ModelName>,
        field_name: FieldName,
        collection_name: CollectionName,
        column_name: DataConnectorColumnName,
    },
    #[error("procedure {procedure_name} is not defined in data connector {db_name}")]
    NoSuchProcedure {
        db_name: Qualified<DataConnectorName>,
        command_name: Qualified<CommandName>,
        procedure_name: ProcedureName,
    },
    #[error("function {function_name} is not defined in data connector {db_name}")]
    NoSuchFunction {
        db_name: Qualified<DataConnectorName>,

View on GitHub (pinned to 724551b9ae)

Solutions

1. Confirm the column exists on the underlying table with exact name/case
2. Update the field mapping's column_name in metadata to the current column
3. Refresh the connector's schema cache so it reflects recent DDL
4. If the column is gone intentionally, remove the field mapping

Example fix

// before
"field_mappings": { "name": { "column": "full_name" } }
// after
"field_mappings": { "fullName": { "column": "full_name" } }

let coll = schema.collections.iter().find(|c| c.name == collection_name).unwrap();
let cols: HashSet<_> = coll.columns.keys().collect();
for field in field_mappings {
    assert!(cols.contains(&field.column_name), "column {} missing on {}", field.column_name, collection_name);
}

fn column_exists(name: &DataConnectorColumnName, coll: &NdcCollection) -> bool {
    coll.columns.contains_key(name)
}

Match NoSuchColumn and report the model field, expected column, and the collection's available columns.

When it happens

Trigger: A field mapping referencing a column dropped/renamed in the database; column name case mismatch; connector schema stale after DDL; mapping copied from another table with different column names.

Common situations: Database migrations renaming columns; multiple environments with schema drift; hand-authored field mappings; connectors with case-sensitive column naming.

Related errors

• the type {unknown_ndc_type:} is not defined as an object typ
• collection {collection_name} is not defined in data connecto
• argument {argument_name} is not defined for collection {coll
• procedure {procedure_name} is not defined in data connector
• unable to parse server endpoint: %w

AI-assisted analysis of hasura/graphql-engine@724551b9ae (2026-08-28). Data as JSON: /api/errors/43d2a206a953311b. Report an issue: GitHub.