hasura/graphql-engine · error · NDCValidationError

column {column_name} is not defined in function/procedure {f

Error message

column {column_name} is not defined in function/procedure {func_proc_name} in data connector {db_name}

What it means

A function/procedure command's field mapping or result shape references a column that the connector's function/procedure does not declare. The resolver validates that every column used in argument/result mappings of a command exists on the underlying NDC function or procedure.

Source

Thrown at v3/crates/metadata-resolve/src/helpers/ndc_validation.rs:65

        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>,
        command_name: Qualified<CommandName>,
        function_name: FunctionName,
    },
    #[error(
        "column {column_name} is not defined in function/procedure {func_proc_name} in data connector {db_name}"
    )]
    NoSuchColumnForCommand {
        db_name: Qualified<DataConnectorName>,
        command_name: Qualified<CommandName>,
        field_name: FieldName,
        func_proc_name: String,
        column_name: DataConnectorColumnName,
    },
    #[error(
        "column {column_name} has type {column_type} in collection {collection_name} in data connector {db_name}, not type {field_type}"
    )]
    ColumnTypeDoesNotMatch {
        db_name: DataConnectorName,
        model_name: ModelName,
        field_name: FieldName,
        collection_name: CollectionName,
        column_name: DataConnectorColumnName,

View on GitHub (pinned to 724551b9ae)

Solutions

1. Check the function/procedure's actual output columns in the connector schema and fix the field mapping in the command definition
2. If the column was renamed in the database, update the metadata to use the new column name
3. Refresh the connector's schema so the resolver sees current columns

Example fix

# before
output_type:
  type: object
  fields:
    user_email: { column: usr_email }  # column not returned by function
# after
output_type:
  type: object
  fields:
    user_email: { column: user_email }

let cols: HashSet<_> = ndc_function.returns.columns();
assert!(cols.contains(&expected_column));

When it happens

Trigger: Adding a mapped field/column in a command's output type that is not among the columns returned by the configured function or procedure; changing the function's return columns without updating command metadata.

Common situations: SELECT list of a database function changed; column renamed; copy-pasting command metadata and forgetting to update column mappings; stale connector schema.

Related errors

• function {function_name} is not defined in data connector {d
• column {column_name} is not defined in collection {collectio
• procedure {procedure_name} is not defined in data connector
• mapping for type {type_name} of command {command_name} is no
• Result type of function/procedure {function_or_procedure_nam

AI-assisted analysis of hasura/graphql-engine@724551b9ae (2026-08-28). Data as JSON: /api/errors/2b722fddac281122. Report an issue: GitHub.