{"record":{"id":"515777b421fdc981","repo":"apache/superset","slug":"validator-s-was-unable-to-check-your-query-plea","errorCode":null,"errorMessage":"%(validator)s was unable to check your query.\nPlease recheck your query.\nException: %(ex)s","messagePattern":"(.+?) was unable to check your query\\.\nPlease recheck your query\\.\nException: (.+?)","errorType":"validation","errorClass":"ValidatorSQL400Error","httpStatus":400,"severity":"error","filePath":"superset/commands/database/validate_sql.py","lineNumber":143,"sourceCode":"            )\n            raise ValidatorSQL400Error(superset_error) from ex\n        except Exception as ex:\n            logger.exception(ex)\n            superset_error = SupersetError(\n                message=__(\n                    \"%(validator)s was unable to check your query.\\n\"\n                    \"Please recheck your query.\\n\"\n                    \"Exception: %(ex)s\",\n                    validator=self._validator.name,\n                    ex=ex,\n                ),\n                error_type=SupersetErrorType.GENERIC_DB_ENGINE_ERROR,\n                level=ErrorLevel.ERROR,\n            )\n\n            # Return as a 400 if the database error message says we got a 4xx error\n            if re.search(r\"([\\W]|^)4\\d{2}([\\W]|$)\", str(ex)):\n                raise ValidatorSQL400Error(superset_error) from ex\n            raise ValidatorSQLError(superset_error) from ex\n\n    def validate(self) -> None:\n        # Validate/populate model exists\n        self._model = DatabaseDAO.find_by_id(self._model_id)\n        if not self._model:\n            raise DatabaseNotFoundError()\n\n        spec = self._model.db_engine_spec\n        validators_by_engine = app.config[\"SQL_VALIDATORS_BY_ENGINE\"]\n        if not validators_by_engine or spec.engine not in validators_by_engine:\n            raise NoValidatorConfigFoundError(\n                SupersetError(\n                    message=__(\n                        \"no SQL validator is configured for %(engine_spec)s\",\n                        engine_spec=spec.engine,\n                    ),\n                    error_type=SupersetErrorType.GENERIC_DB_ENGINE_ERROR,","sourceCodeStart":125,"sourceCodeEnd":161,"githubUrl":"https://github.com/apache/superset/blob/f4587218dd19d046c3e4d00063e7d27f8a2ed354/superset/commands/database/validate_sql.py#L125-L161","documentation":"The generic except-Exception handler in validate_sql wraps any failure of self._validator.validate(sql, catalog, schema, model) into a SupersetError saying '%(validator)s was unable to check your query... Exception: %(ex)s'. This is the catch-all for the external SQL validator backend (e.g., the Presto/Trino validator) blowing up, including the utils.timeout exception when validation exceeds SQLLAB_VALIDATION_TIMEOUT seconds. The error becomes ValidatorSQL400Error if the exception text contains a standalone 3-digit 4xx code (regex `([\\W]|^)4\\d{2}([\\W]|$)`), otherwise ValidatorSQLError (422).","triggerScenarios":"POST /api/v1/database/validate_sql for an engine with a configured validator where: the validator HTTP service (e.g., a Presto validator endpoint) is down or returns an error; the query takes longer than SQLLAB_VALIDATION_TIMEOUT seconds ('The query exceeded the N seconds timeout.'); the validator client raises a network or parsing exception.","commonSituations":"SQLLAB_VALIDATION_TIMEOUT left at default while validating huge queries; the validator service URL in config is stale/unreachable in the deployment; validator version mismatch with the engine; proxies returning HTML error pages that the client cannot parse (surfacing as a generic exception).","solutions":["If the message says the query exceeded the timeout, raise SQLLAB_VALIDATION_TIMEOUT in superset_config.py or validate a smaller query.","Verify the validator backend configured under SQL_VALIDATORS_BY_ENGINE is deployed, reachable from Superset, and healthy.","Check the logged exception (logger.exception) for the root cause — 4xx-class messages become 400, everything else 422.","If the validator is flaky or unnecessary, remove the engine from SQL_VALIDATORS_BY_ENGINE so the UI skips server-side validation."],"exampleFix":"# superset_config.py — before\nSQLLAB_VALIDATION_TIMEOUT = 2\n\n# after\nSQLLAB_VALIDATION_TIMEOUT = 15","handlingStrategy":"retry","validationCode":"# Verify the validator backend is up before submitting validation\ndef validator_backend_healthy(app, engine: str) -> bool:\n    from superset.sql_validators import get_validator_by_name\n    name = app.config[\"SQL_VALIDATORS_BY_ENGINE\"].get(engine)\n    validator = get_validator_by_name(name) if name else None\n    return validator is not None and getattr(validator, \"available\", lambda: True)()","typeGuard":null,"tryCatchPattern":"from superset.commands.database.exceptions import ValidatorSQLError, ValidatorSQL400Error\nimport time\nfor attempt in range(2):\n    try:\n        return ValidatorSQLCommand(db_id, payload).run()\n    except ValidatorSQL400Error:\n        raise  # client/query problem — not retryable\n    except ValidatorSQLError as ex:\n        if \"timeout\" in str(ex).lower() and attempt == 0:\n            time.sleep(1)\n            continue  # transient timeout: retry once\n        raise","preventionTips":["Size SQLLAB_VALIDATION_TIMEOUT above your p95 validation latency.","Monitor the validator service (deployment health check) so outages are caught before users.","Exclude engines with no reliable validator from SQL_VALIDATORS_BY_ENGINE instead of letting calls fail generically."],"tags":["sql-validation","timeout","validator-backend","flask-api"],"backgroundTag":null,"analyzedSha":"f4587218dd19d046c3e4d00063e7d27f8a2ed354","analyzedAt":"2026-08-14T22:39:27.425Z","schemaVersion":2},"datasetVersion":"2026-08-15T17:31:12.345Z"}