fix(select): classify function argument planner errors

crates/s3select-api/src/lib.rs

@@ -14,7 +14,12 @@
 
 #![recursion_limit = "256"]
 
-use datafusion::{common::DataFusionError, sql::sqlparser::parser::ParserError};
+use datafusion::{
+    arrow::error::ArrowError,
+    common::{DataFusionError, SchemaError},
+    parquet::errors::ParquetError,
+    sql::sqlparser::parser::ParserError,
+};
 use std::{error::Error as StdError, fmt::Display};
 use thiserror::Error;
 
@@ -67,23 +72,88 @@ pub enum QueryError {
     StoreError { e: String },
 }
 
-#[derive(Debug, Error)]
-#[non_exhaustive]
-pub enum S3SelectPolicyError {
+#[derive(Clone, Debug, Error, PartialEq, Eq)]
+pub enum SelectError {
+    #[error("The file is not in a supported compression format. Only GZIP and BZIP2 are supported.")]
+    InvalidCompressionFormat,
+
+    #[error("The data source type is not valid. Only CSV, JSON, and Parquet are supported.")]
+    InvalidDataSource,
+
+    #[error(
+        "Object decompression failed. Check that the object is properly compressed using the format specified in the request."
+    )]
+    TruncatedInput,
+
+    #[error("An error occurred while parsing the CSV file. Check the file and try again.")]
+    CsvParsingError,
+
+    #[error("An error occurred while parsing the JSON file. Check the file and try again.")]
+    JsonParsingError,
+
+    #[error("An error occurred while parsing the Parquet file. Check the file and try again.")]
+    ParquetParsingError,
+
+    #[error("{message}")]
+    ParseSelectFailure { message: String },
+
+    #[error("The SQL expression is invalid.")]
+    InvalidQuery,
+
+    #[error("The SQL expression contains a data type that is not valid.")]
+    InvalidDataType,
+
+    #[error("An incorrect argument type was specified in a function call in the SQL expression.")]
+    IncorrectSqlFunctionArgumentType,
+
+    #[error("The data source path in the SQL expression is not supported.")]
+    DataSourcePathUnsupported,
+
     #[error("Unsupported S3 Select SQL structure: {message}")]
     UnsupportedSqlStructure { message: String },
 
+    #[error("We encountered an unsupported SQL operation.")]
+    UnsupportedSqlOperation,
+
+    #[error("A column name or a path provided does not exist in the SQL expression.")]
+    EvaluatorBindingDoesNotExist,
+
+    #[error("The field name matches to multiple fields in the file. Check the SQL expression and the file, and try again.")]
+    AmbiguousFieldName,
+
+    #[error("The value of a parameter in ScanRange element is invalid. Check the service API documentation and try again.")]
+    InvalidScanRange,
+
     #[error("S3 Select query concurrency limit reached")]
     QueryConcurrencyLimit,
 
     #[error("S3 Select query exceeded the {seconds}-second execution limit")]
     QueryTimeout { seconds: u64 },
+
+    #[error("S3 Select query resource limit exceeded")]
+    ResourceExhausted,
+
+    #[error("The specified bucket does not exist.")]
+    BucketNotFound,
+
+    #[error("The specified key does not exist.")]
+    ObjectNotFound,
+
+    #[error("The query was canceled")]
+    Canceled,
+
+    #[error("An internal error occurred.")]
+    InternalError,
 }
 
+pub type S3SelectPolicyError = SelectError;
+
+const MAX_ERROR_SOURCE_DEPTH: usize = 16;
+
 impl QueryError {
     fn source_error<T: StdError + 'static>(&self) -> Option<&T> {
         let mut err: &(dyn StdError + 'static) = self;
-        for _ in 0..16 {
+        for _ in 0..MAX_ERROR_SOURCE_DEPTH {
             if let Some(source) = err.downcast_ref::<T>() {
                 return Some(source);
             }
@@ -99,10 +169,113 @@ impl QueryError {
     pub fn s3_select_policy_error(&self) -> Option<&S3SelectPolicyError> {
         self.source_error()
     }
+
+    pub fn select_error(&self) -> SelectError {
+        let mut err: &(dyn StdError + 'static) = match self {
+            Self::Datafusion { source } => source.as_ref(),
+            _ => self,
+        };
+        for _ in 0..MAX_ERROR_SOURCE_DEPTH {
+            if let Some(select_error) = classify_select_error_source(err) {
+                return select_error;
+            }
+            let Some(source) = err.source() else {
+                break;
+            };
+            err = source;
+        }
+
+        match self {
+            QueryError::NotImplemented { .. } => SelectError::UnsupportedSqlOperation,
+            QueryError::MultiStatement { .. } => SelectError::UnsupportedSqlStructure {
+                message: "multiple SQL statements are not supported".to_string(),
+            },
+            QueryError::BuildQueryDispatcher { .. } | QueryError::FunctionExists { .. } | QueryError::StoreError { .. } => {
+                SelectError::InternalError
+            }
+            QueryError::Cancel => SelectError::Canceled,
+            QueryError::FunctionNotExists { .. } => SelectError::InvalidQuery,
+            QueryError::Datafusion { .. } | QueryError::Parser { .. } => SelectError::InternalError,
+        }
+    }
 }
 
-impl From<S3SelectPolicyError> for QueryError {
-    fn from(value: S3SelectPolicyError) -> Self {
+fn classify_select_error_source(err: &(dyn StdError + 'static)) -> Option<SelectError> {
+    if let Some(error) = err.downcast_ref::<SelectError>() {
+        return Some(error.clone());
+    }
+    if let Some(error) = err.downcast_ref::<object_store::SelectObjectStoreError>() {
+        return Some(error.select_error());
+    }
+    if let Some(error) = err.downcast_ref::<datafusion::object_store::Error>() {
+        return match error {
+            datafusion::object_store::Error::NotFound { source, .. } => Some(
+                source
+                    .downcast_ref::<object_store::SelectObjectStoreError>()
+                    .map_or(SelectError::ObjectNotFound, object_store::SelectObjectStoreError::select_error),
+            ),
+            _ => None,
+        };
+    }
+    if let Some(error) = err.downcast_ref::<ParserError>() {
+        return Some(SelectError::ParseSelectFailure {
+            message: error.to_string(),
+        });
+    }
+    if let Some(error) = err.downcast_ref::<ArrowError>() {
+        return match error {
+            ArrowError::CsvError(_) => Some(SelectError::CsvParsingError),
+            ArrowError::JsonError(_) => Some(SelectError::JsonParsingError),
+            ArrowError::ParquetError(_) => Some(SelectError::ParquetParsingError),
+            ArrowError::CastError(_) | ArrowError::ParseError(_) => Some(SelectError::InvalidDataType),
+            ArrowError::MemoryError(_) => Some(SelectError::ResourceExhausted),
+            ArrowError::ExternalError(_) | ArrowError::IoError(_, _) => None,
+            _ => Some(SelectError::InternalError),
+        };
+    }
+    if let Some(error) = err.downcast_ref::<ParquetError>() {
+        return match error {
+            ParquetError::External(_) => None,
+            _ => Some(SelectError::ParquetParsingError),
+        };
+    }
+    if let Some(error) = err.downcast_ref::<SchemaError>() {
+        return Some(match error {
+            SchemaError::FieldNotFound { .. } => SelectError::EvaluatorBindingDoesNotExist,
+            SchemaError::AmbiguousReference { .. }
+            | SchemaError::DuplicateQualifiedField { .. }
+            | SchemaError::DuplicateUnqualifiedField { .. } => SelectError::AmbiguousFieldName,
+        });
+    }
+    if let Some(error) = err.downcast_ref::<DataFusionError>() {
+        return match error {
+            DataFusionError::NotImplemented(_) => Some(SelectError::UnsupportedSqlOperation),
+            DataFusionError::Plan(_) => Some(SelectError::InvalidQuery),
+            DataFusionError::ResourcesExhausted(_) => Some(SelectError::ResourceExhausted),
+            DataFusionError::Internal(_)
+            | DataFusionError::Execution(_)
+            | DataFusionError::Configuration(_)
+            | DataFusionError::Substrait(_)
+            | DataFusionError::Ffi(_) => Some(SelectError::InternalError),
+            DataFusionError::ArrowError(_, _)
+            | DataFusionError::ParquetError(_)
+            | DataFusionError::ObjectStore(_)
+            | DataFusionError::IoError(_)
+            | DataFusionError::SQL(_, _)
+            | DataFusionError::SchemaError(_, _)
+            | DataFusionError::ExecutionJoin(_)
+            | DataFusionError::External(_)
+            | DataFusionError::Context(_, _)
+            | DataFusionError::Diagnostic(_, _)
+            | DataFusionError::Collection(_)
+            | DataFusionError::Shared(_) => None,
+        };
+    }
+    None
+}
+
+impl From<SelectError> for QueryError {
+    fn from(value: SelectError) -> Self {
         Self::Datafusion {
             source: Box::new(DataFusionError::External(Box::new(value))),
         }
@@ -161,7 +334,7 @@ mod tests {
         };
         assert_eq!(err.to_string(), "Multi-statement not allow, found num:2, sql:SELECT 1; SELECT 2;");
 
-        let err = S3SelectPolicyError::UnsupportedSqlStructure {
+        let err = SelectError::UnsupportedSqlStructure {
             message: "JOIN is not supported".to_string(),
         };
         assert_eq!(err.to_string(), "Unsupported S3 Select SQL structure: JOIN is not supported");
@@ -170,11 +343,11 @@ mod tests {
         assert_eq!(err.to_string(), "The query has been canceled");
 
         assert_eq!(
-            S3SelectPolicyError::QueryConcurrencyLimit.to_string(),
+            SelectError::QueryConcurrencyLimit.to_string(),
             "S3 Select query concurrency limit reached"
         );
         assert_eq!(
-            S3SelectPolicyError::QueryTimeout { seconds: 300 }.to_string(),
+            SelectError::QueryTimeout { seconds: 300 }.to_string(),
             "S3 Select query exceeded the 300-second execution limit"
         );
 
@@ -223,12 +396,132 @@ mod tests {
 
     #[test]
     fn policy_error_is_recoverable_from_query_error() {
-        let err: QueryError = S3SelectPolicyError::QueryTimeout { seconds: 300 }.into();
+        let err: QueryError = SelectError::QueryTimeout { seconds: 300 }.into();
 
-        assert!(matches!(
-            err.s3_select_policy_error(),
-            Some(S3SelectPolicyError::QueryTimeout { seconds: 300 })
-        ));
+        assert!(matches!(err.s3_select_policy_error(), Some(SelectError::QueryTimeout { seconds: 300 })));
+    }
+
+    #[test]
+    fn query_error_classifies_data_errors_without_display_matching() {
+        let cases = [
+            (
+                DataFusionError::ArrowError(Box::new(ArrowError::CsvError("private csv detail".to_string())), None),
+                SelectError::CsvParsingError,
+            ),
+            (
+                DataFusionError::ArrowError(Box::new(ArrowError::JsonError("private json detail".to_string())), None),
+                SelectError::JsonParsingError,
+            ),
+            (
+                DataFusionError::ParquetError(Box::new(ParquetError::General("private parquet detail".to_string()))),
+                SelectError::ParquetParsingError,
+            ),
+            (
+                DataFusionError::External(Box::new(SelectError::TruncatedInput)),
+                SelectError::TruncatedInput,
+            ),
+            (
+                DataFusionError::ArrowError(
+                    Box::new(ArrowError::InvalidArgumentError("private implementation detail".to_string())),
+                    None,
+                ),
+                SelectError::InternalError,
+            ),
+            (
+                DataFusionError::ArrowError(Box::new(ArrowError::CastError("invalid cast".to_string())), None),
+                SelectError::InvalidDataType,
+            ),
+            (
+                DataFusionError::ArrowError(Box::new(ArrowError::MemoryError("query memory limit".to_string())), None),
+                SelectError::ResourceExhausted,
+            ),
+            (
+                DataFusionError::Execution("private execution detail".to_string()),
+                SelectError::InternalError,
+            ),
+            (DataFusionError::Plan("invalid expression".to_string()), SelectError::InvalidQuery),
+            (
+                DataFusionError::NotImplemented("unsupported expression".to_string()),
+                SelectError::UnsupportedSqlOperation,
+            ),
+            (
+                DataFusionError::SchemaError(
+                    Box::new(SchemaError::FieldNotFound {
+                        field: Box::new(datafusion::common::Column::from_name("missing")),
+                        valid_fields: Vec::new(),
+                    }),
+                    Box::new(None),
+                ),
+                SelectError::EvaluatorBindingDoesNotExist,
+            ),
+            (
+                DataFusionError::SchemaError(
+                    Box::new(SchemaError::AmbiguousReference {
+                        field: Box::new(datafusion::common::Column::from_name("duplicate")),
+                    }),
+                    Box::new(None),
+                ),
+                SelectError::AmbiguousFieldName,
+            ),
+        ];
+
+        for (source, expected) in cases {
+            let error = QueryError::from(source);
+            assert_eq!(error.select_error(), expected, "wrong classification for {error:?}");
+        }
+    }
+
+    #[test]
+    fn query_error_preserves_typed_object_store_classification() {
+        let bucket_error = QueryError::from(DataFusionError::ObjectStore(Box::new(datafusion::object_store::Error::NotFound {
+            path: "private-bucket/private-object".to_string(),
+            source: Box::new(object_store::SelectObjectStoreError::BucketNotFound {
+                source: SelectStorageError::BucketNotFound("private-bucket".to_string()),
+            }),
+        })));
+        let object_error = QueryError::from(DataFusionError::ObjectStore(Box::new(datafusion::object_store::Error::NotFound {
+            path: "private-bucket/private-object".to_string(),
+            source: Box::new(object_store::SelectObjectStoreError::ObjectNotFound {
+                source: SelectStorageError::ObjectNotFound("private-bucket".to_string(), "private-object".to_string()),
+            }),
+        })));
+        let scan_range_error =
+            QueryError::from(DataFusionError::ObjectStore(Box::new(datafusion::object_store::Error::Generic {
+                store: "test",
+                source: Box::new(object_store::SelectObjectStoreError::InvalidScanRange),
+            })));
+        let storage_error = QueryError::from(DataFusionError::ObjectStore(Box::new(datafusion::object_store::Error::Generic {
+            store: "test",
+            source: Box::new(object_store::SelectObjectStoreError::Storage {
+                source: SelectStorageError::LessData,
+            }),
+        })));
+
+        assert_eq!(bucket_error.select_error(), SelectError::BucketNotFound);
+        assert_eq!(object_error.select_error(), SelectError::ObjectNotFound);
+        assert_eq!(scan_range_error.select_error(), SelectError::InvalidScanRange);
+        assert_eq!(storage_error.select_error(), SelectError::InternalError);
+    }
+
+    #[test]
+    fn select_error_source_traversal_stops_at_the_depth_bound() {
+        #[derive(Debug)]
+        struct CyclicError;
+
+        impl std::fmt::Display for CyclicError {
+            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+                f.write_str("cyclic error")
+            }
+        }
+
+        impl StdError for CyclicError {
+            fn source(&self) -> Option<&(dyn StdError + 'static)> {
+                Some(self)
+            }
+        }
+
+        let error = QueryError::from(DataFusionError::External(Box::new(CyclicError)));
+        assert_eq!(error.select_error(), SelectError::InternalError);
     }
 
     #[test]

crates/s3select-api/src/object_store.rs

@@ -13,7 +13,7 @@
 // limitations under the License.
 
 use crate::{
-    PrepareSelectObjectSnapshotError, SELECT_DEFAULT_READ_BUFFER_SIZE, SelectGetObjectReader, SelectObjectOptions,
+    PrepareSelectObjectSnapshotError, SELECT_DEFAULT_READ_BUFFER_SIZE, SelectError, SelectGetObjectReader, SelectObjectOptions,
     SelectObjectSnapshot, SelectObjectSnapshotReadError, SelectStorageError, SelectStore, SnapshotConsistencyError,
     query::{
         parser::RustFsDialect,
@@ -115,6 +115,38 @@ pub(crate) enum EcObjectStoreBuildError {
     Snapshot(#[source] SnapshotConsistencyError),
 }
 
+#[derive(Debug, thiserror::Error)]
+pub(crate) enum SelectObjectStoreError {
+    #[error("SelectObjectContent bucket does not exist")]
+    BucketNotFound {
+        #[source]
+        source: SelectStorageError,
+    },
+    #[error("SelectObjectContent object does not exist")]
+    ObjectNotFound {
+        #[source]
+        source: SelectStorageError,
+    },
+    #[error("SelectObjectContent storage failure")]
+    Storage {
+        #[source]
+        source: SelectStorageError,
+    },
+    #[error("SelectObjectContent ScanRange is invalid")]
+    InvalidScanRange,
+}
+
+impl SelectObjectStoreError {
+    pub(crate) fn select_error(&self) -> SelectError {
+        match self {
+            Self::BucketNotFound { .. } => SelectError::BucketNotFound,
+            Self::ObjectNotFound { .. } => SelectError::ObjectNotFound,
+            Self::InvalidScanRange => SelectError::InvalidScanRange,
+            Self::Storage { .. } => SelectError::InternalError,
+        }
+    }
+}
+
 #[derive(Clone, Copy, Debug)]
 pub struct SelectScanRange {
     start: u64,
@@ -502,8 +534,7 @@ fn map_prepare_snapshot_error(bucket: &str, object: &str, err: PrepareSelectObje
 }
 
 fn map_build_error_to_s3(error: EcObjectStoreBuildError) -> S3Error {
-    let message = error.to_string();
-    let mut s3_error = S3Error::with_message(S3ErrorCode::InternalError, message);
+    let mut s3_error = S3Error::with_message(S3ErrorCode::InternalError, SelectError::InternalError.to_string());
     s3_error.set_source(Box::new(error));
     s3_error
 }
@@ -519,15 +550,21 @@ fn snapshot_read_error(bucket: &str, object: &str, err: SelectObjectSnapshotRead
 }
 
 fn map_storage_error(bucket: &str, object: &str, err: SelectStorageError) -> o_Error {
-    if select_is_err_bucket_not_found(&err) || select_is_err_object_not_found(&err) || select_is_err_version_not_found(&err) {
+    if select_is_err_bucket_not_found(&err) {
         return o_Error::NotFound {
             path: format!("{bucket}/{object}"),
-            source: Box::new(err),
+            source: Box::new(SelectObjectStoreError::BucketNotFound { source: err }),
+        };
+    }
+    if select_is_err_object_not_found(&err) || select_is_err_version_not_found(&err) {
+        return o_Error::NotFound {
+            path: format!("{bucket}/{object}"),
+            source: Box::new(SelectObjectStoreError::ObjectNotFound { source: err }),
         };
     }
     o_Error::Generic {
         store: "EcObjectStore",
-        source: Box::new(err),
+        source: Box::new(SelectObjectStoreError::Storage { source: err }),
     }
 }
 
@@ -602,7 +639,7 @@ fn parse_scan_range_from_bounds(
 fn invalid_scan_range_store_error() -> o_Error {
     o_Error::Generic {
         store: "EcObjectStore",
-        source: format!("ScanRange: {INVALID_SCAN_RANGE_MESSAGE}").into(),
+        source: Box::new(SelectObjectStoreError::InvalidScanRange),
     }
 }
 
@@ -1150,7 +1187,11 @@ where
         })?
         .map_err(|e| o_Error::Generic {
             store: "EcObjectStore",
-            source: Box::new(e),
+            source: if e.kind() == std::io::ErrorKind::InvalidData {
+                Box::new(SelectError::JsonParsingError)
+            } else {
+                Box::new(e)
+            },
         })?;
 
         // ── 3. Yield phase (one Bytes per NDJSON line) ───────────────────
@@ -1341,12 +1382,13 @@ mod test {
         SELECT_DEFAULT_READ_BUFFER_SIZE, SelectObjectOptions, SelectObjectSnapshot, SelectScanRange, SnapshotConsistencyError,
         bytes_stream, convert_csv_delimiter_stream, convert_field_delimiter_stream, convert_record_delimiter_stream,
         extract_json_sub_path_from_expression, find_delimiter, flatten_json_document_to_ndjson, http_range_spec_from_get_range,
-        json_document_ndjson_stream, json_document_ndjson_stream_with_parser, scan_range_from_bounds, scan_range_stream,
-        select_read_headers, snapshot_last_modified, validate_json_document_size,
+        json_document_ndjson_stream, json_document_ndjson_stream_with_parser, map_storage_error, scan_range_from_bounds,
+        scan_range_stream, select_read_headers, snapshot_last_modified, validate_json_document_size,
     };
     use crate::query::session::{QueryExecutionGuard, QueryExecutionOwner, QueryExecutionTracker};
     use crate::storage_api::SelectPutObjReader;
     use crate::storage_api::object_store::ObjectIO as _;
+    use crate::{QueryError, SelectError, SelectStorageError};
     use bytes::Bytes;
     use datafusion::{
         common::DataFusionError,
@@ -2688,6 +2730,69 @@ mod test {
         assert!(output.next().await.is_none());
     }
 
+    #[tokio::test]
+    async fn malformed_json_document_stream_has_typed_select_error() {
+        let input = b"{bad".to_vec();
+        let memory_pool: Arc<dyn MemoryPool> =
+            Arc::new(GreedyMemoryPool::new(input.len() * JSON_DOCUMENT_MEMORY_RESERVATION_MULTIPLIER));
+        let mut output = json_document_ndjson_stream(
+            Box::new(std::io::Cursor::new(input.clone())),
+            input.len() as u64,
+            None,
+            memory_pool,
+            None,
+        );
+
+        let source = output
+            .next()
+            .await
+            .expect("malformed JSON should produce one stream error")
+            .expect_err("malformed JSON DOCUMENT must fail");
+        let error = QueryError::from(DataFusionError::ObjectStore(Box::new(source)));
+
+        assert_eq!(error.select_error(), SelectError::JsonParsingError);
+        assert!(output.next().await.is_none());
+    }
+
+    #[test]
+    fn storage_error_mapper_preserves_protocol_classification() {
+        let classify = |source| QueryError::from(DataFusionError::ObjectStore(Box::new(source))).select_error();
+
+        assert_eq!(
+            classify(map_storage_error(
+                "private-bucket",
+                "private-object",
+                SelectStorageError::BucketNotFound("private-bucket".to_string()),
+            )),
+            SelectError::BucketNotFound
+        );
+        assert_eq!(
+            classify(map_storage_error(
+                "private-bucket",
+                "private-object",
+                SelectStorageError::ObjectNotFound("private-bucket".to_string(), "private-object".to_string()),
+            )),
+            SelectError::ObjectNotFound
+        );
+        assert_eq!(
+            classify(map_storage_error("private-bucket", "private-object", SelectStorageError::LessData)),
+            SelectError::InternalError
+        );
+        assert_eq!(
+            classify(scan_range_from_bounds(Some(10), None, 10).expect_err("out-of-bounds range must fail")),
+            SelectError::InvalidScanRange
+        );
+        let parquet_source = map_storage_error(
+            "private-bucket",
+            "private-object",
+            SelectStorageError::ObjectNotFound("private-bucket".to_string(), "private-object".to_string()),
+        );
+        let parquet_error = QueryError::from(DataFusionError::ParquetError(Box::new(
+            datafusion::parquet::errors::ParquetError::External(Box::new(parquet_source)),
+        )));
+        assert_eq!(parquet_error.select_error(), SelectError::ObjectNotFound);
+    }
+
     #[test]
     fn test_json_document_size_error_is_resource_exhausted() {
         assert!(validate_json_document_size(super::MAX_JSON_DOCUMENT_BYTES).is_ok());

crates/s3select-api/src/query/session.rs

@@ -433,7 +433,7 @@ impl SessionCtxFactory {
             let path = Path::from(context.input.key.clone());
             store.put(&path, data_bytes.into()).await.map_err(|e| {
                 error!("put data into memory failed: {}", e.to_string());
-                QueryError::StoreError { e: e.to_string() }
+                QueryError::from(DataFusionError::from(e))
             })?;
 
             df_session_state.with_object_store(&store_url, store).build()
@@ -477,16 +477,11 @@ fn test_parquet_bytes() -> QueryResult<Vec<u8>> {
 
     let mut bytes = Vec::new();
     {
-        let mut writer =
-            ArrowWriter::try_new(&mut bytes, schema, None).map_err(|e| QueryError::StoreError { e: e.to_string() })?;
-        writer
-            .write(&first_batch)
-            .map_err(|e| QueryError::StoreError { e: e.to_string() })?;
-        writer.flush().map_err(|e| QueryError::StoreError { e: e.to_string() })?;
-        writer
-            .write(&second_batch)
-            .map_err(|e| QueryError::StoreError { e: e.to_string() })?;
-        writer.close().map_err(|e| QueryError::StoreError { e: e.to_string() })?;
+        let mut writer = ArrowWriter::try_new(&mut bytes, schema, None).map_err(DataFusionError::from)?;
+        writer.write(&first_batch).map_err(DataFusionError::from)?;
+        writer.flush().map_err(DataFusionError::from)?;
+        writer.write(&second_batch).map_err(DataFusionError::from)?;
+        writer.close().map_err(DataFusionError::from)?;
     }
     Ok(bytes)
 }
@@ -509,7 +504,8 @@ fn test_parquet_batch(
             Arc::new(Int32Array::from(salaries.to_vec())),
         ],
     )
-    .map_err(|e| QueryError::StoreError { e: e.to_string() })
+    .map_err(DataFusionError::from)
+    .map_err(QueryError::from)
 }
 
 #[cfg(test)]

crates/s3select-query/src/dispatcher/manager.rs

@@ -38,7 +38,7 @@ use datafusion::{
 use futures::Stream;
 use parking_lot::Mutex;
 use rustfs_s3select_api::{
-    QueryError, QueryResult, S3SelectPolicyError,
+    QueryError, QueryResult, SelectError,
     query::{
         Query,
         ast::ExtStatement,
@@ -128,7 +128,7 @@ impl QueryDispatcher for SimpleQueryDispatcher {
             .query_admission
             .clone()
             .try_acquire_owned()
-            .map_err(|_| QueryError::from(S3SelectPolicyError::QueryConcurrencyLimit))?;
+            .map_err(|_| QueryError::from(SelectError::QueryConcurrencyLimit))?;
         Ok(QueryAdmission::new(Arc::new(permit)))
     }
 
@@ -245,7 +245,7 @@ impl SimpleQueryDispatcher {
                     .query_admission
                     .clone()
                     .try_acquire_owned()
-                    .map_err(|_| QueryError::from(S3SelectPolicyError::QueryConcurrencyLimit))?;
+                    .map_err(|_| QueryError::from(SelectError::QueryConcurrencyLimit))?;
                 Arc::new(permit)
             }
         };
@@ -293,7 +293,7 @@ impl SimpleQueryDispatcher {
     ) -> QueryResult<T> {
         let deadline = query_tracker.deadline();
         let timeout_error = || {
-            S3SelectPolicyError::QueryTimeout {
+            SelectError::QueryTimeout {
                 seconds: query_tracker.timeout_seconds(),
             }
             .into()
@@ -343,11 +343,11 @@ impl SimpleQueryDispatcher {
             return QueryError::Cancel;
         }
         match query_tracker.status() {
-            QueryExecutionStatus::TimedOut => S3SelectPolicyError::QueryTimeout {
+            QueryExecutionStatus::TimedOut => SelectError::QueryTimeout {
                 seconds: query_tracker.timeout_seconds(),
             }
             .into(),
-            QueryExecutionStatus::Active if Instant::now() >= query_tracker.deadline() => S3SelectPolicyError::QueryTimeout {
+            QueryExecutionStatus::Active if Instant::now() >= query_tracker.deadline() => SelectError::QueryTimeout {
                 seconds: query_tracker.timeout_seconds(),
             }
             .into(),
@@ -430,15 +430,11 @@ impl SimpleQueryDispatcher {
                         } else if *info == *USE {
                             file_format = file_format.with_has_header(true);
                         } else {
-                            return Err(QueryError::NotImplemented {
-                                err: "unsupported FileHeaderInfo".to_string(),
-                            });
+                            return Err(SelectError::InvalidDataSource.into());
                         }
                     }
                     _ => {
-                        return Err(QueryError::NotImplemented {
-                            err: "unsupported FileHeaderInfo".to_string(),
-                        });
+                        return Err(SelectError::InvalidDataSource.into());
                     }
                 }
                 if let Some(quote) = csv.quote_character.as_ref() {
@@ -462,9 +458,7 @@ impl SimpleQueryDispatcher {
                     .unwrap_or_else(|| ".json".to_string());
                 (ListingOptions::new(Arc::new(file_format)).with_file_extension(file_ext), false, false)
             } else {
-                return Err(QueryError::NotImplemented {
-                    err: "not support this file type".to_string(),
-                });
+                return Err(SelectError::InvalidDataSource.into());
             };
 
         let resolve_schema = listing_options.infer_schema(session.inner(), &table_path).await?;
@@ -642,7 +636,7 @@ impl Stream for TrackedRecordBatchStream {
 }
 
 fn query_timeout_error(timeout_seconds: u64) -> datafusion::common::DataFusionError {
-    datafusion::common::DataFusionError::External(Box::new(S3SelectPolicyError::QueryTimeout {
+    datafusion::common::DataFusionError::External(Box::new(SelectError::QueryTimeout {
         seconds: timeout_seconds,
     }))
 }
@@ -791,7 +785,7 @@ mod tests {
     };
     use futures::{StreamExt, TryStreamExt, stream};
     use rustfs_s3select_api::{
-        QueryError, QueryResult, S3SelectPolicyError,
+        QueryError, QueryResult, SelectError,
         query::{
             Context as QueryContext, Query,
             dispatcher::QueryDispatcher,
@@ -1338,6 +1332,47 @@ mod tests {
         assert_eq!(dispatcher.memory_limit_bytes, DEFAULT_S3SELECT_MEMORY_LIMIT_BYTES);
     }
 
+    #[tokio::test]
+    async fn invalid_csv_header_info_is_typed_invalid_data_source() {
+        let mut input = test_input();
+        input
+            .request
+            .input_serialization
+            .csv
+            .as_mut()
+            .expect("test input should use CSV")
+            .file_header_info = Some(FileHeaderInfo::from_static("INVALID"));
+        let input = Arc::new(input);
+        let optimizer = Arc::new(CascadeOptimizerBuilder::default().build());
+        let scheduler = Arc::new(LocalScheduler {});
+        let dispatcher = SimpleQueryDispatcherBuilder::default()
+            .with_input(Arc::clone(&input))
+            .with_default_table_provider(Arc::new(BaseTableProvider::default()))
+            .with_session_factory(Arc::new(SessionCtxFactory::new(true)))
+            .with_parser(Arc::new(DefaultParser::default()))
+            .with_query_execution_factory(Arc::new(SqlQueryExecutionFactory::new(optimizer, scheduler)))
+            .with_func_manager(Arc::new(SimpleFunctionMetadataManager::default()))
+            .build()
+            .expect("query dispatcher should build");
+        let query = Query::new(
+            QueryContext {
+                input: Arc::clone(&input),
+            },
+            input.request.expression.clone(),
+        );
+        let query_state_machine = dispatcher
+            .build_query_state_machine(query)
+            .await
+            .expect("query should acquire admission");
+
+        let error = match dispatcher.build_logical_plan(query_state_machine).await {
+            Err(error) => error,
+            Ok(_) => panic!("invalid FileHeaderInfo must fail while building the provider"),
+        };
+
+        assert_eq!(error.select_error(), SelectError::InvalidDataSource);
+    }
+
     #[tokio::test]
     async fn csv_query_uses_custom_record_delimiter_across_file_partitions() {
         const ROW_COUNT: usize = 200_000;
@@ -1420,7 +1455,7 @@ mod tests {
 
         assert!(matches!(
             result,
-            Err(ref err) if matches!(err.s3_select_policy_error(), Some(S3SelectPolicyError::QueryConcurrencyLimit))
+            Err(ref err) if matches!(err.s3_select_policy_error(), Some(SelectError::QueryConcurrencyLimit))
         ));
     }
 
@@ -1474,7 +1509,7 @@ mod tests {
 
         assert!(matches!(
             result,
-            Err(ref err) if matches!(err.s3_select_policy_error(), Some(S3SelectPolicyError::QueryConcurrencyLimit))
+            Err(ref err) if matches!(err.s3_select_policy_error(), Some(SelectError::QueryConcurrencyLimit))
         ));
     }
 
@@ -1571,7 +1606,7 @@ mod tests {
 
         assert!(matches!(
             result,
-            Err(ref err) if matches!(err.s3_select_policy_error(), Some(S3SelectPolicyError::QueryTimeout { seconds: 0 }))
+            Err(ref err) if matches!(err.s3_select_policy_error(), Some(SelectError::QueryTimeout { seconds: 0 }))
         ));
         assert_eq!(admission.available_permits(), 1);
     }
@@ -1601,7 +1636,7 @@ mod tests {
 
         assert!(matches!(
             dispatcher.execute_logical_plan(logical_plan, query_state_machine).await,
-            Err(ref err) if matches!(err.s3_select_policy_error(), Some(S3SelectPolicyError::QueryTimeout { seconds: 300 }))
+            Err(ref err) if matches!(err.s3_select_policy_error(), Some(SelectError::QueryTimeout { seconds: 300 }))
         ));
         assert_eq!(admission.available_permits(), 1);
     }
@@ -1742,7 +1777,7 @@ mod tests {
         assert_eq!(admission.available_permits(), 1);
         assert!(matches!(
             dispatcher.build_logical_plan(query_state_machine).await,
-            Err(ref err) if matches!(err.s3_select_policy_error(), Some(S3SelectPolicyError::QueryTimeout { seconds: 1 }))
+            Err(ref err) if matches!(err.s3_select_policy_error(), Some(SelectError::QueryTimeout { seconds: 1 }))
         ));
     }
 
@@ -1843,7 +1878,7 @@ mod tests {
         release_drop_tx.send(()).expect("release result drop");
         assert!(matches!(
             task.await.expect("deadline task should finish"),
-            Err(ref err) if matches!(err.s3_select_policy_error(), Some(S3SelectPolicyError::QueryTimeout { seconds: 1 }))
+            Err(ref err) if matches!(err.s3_select_policy_error(), Some(SelectError::QueryTimeout { seconds: 1 }))
         ));
         assert_eq!(admission.available_permits(), 1);
     }
@@ -1985,8 +2020,8 @@ mod tests {
             panic!("expected external query error");
         };
         assert!(matches!(
-            source.downcast_ref::<S3SelectPolicyError>(),
-            Some(S3SelectPolicyError::QueryTimeout { seconds: 300 })
+            source.downcast_ref::<SelectError>(),
+            Some(SelectError::QueryTimeout { seconds: 300 })
         ));
         assert!(inner_dropped.load(Ordering::SeqCst));
         assert_eq!(admission.available_permits(), 1);
@@ -2124,8 +2159,8 @@ mod tests {
             panic!("expected external query error");
         };
         assert!(matches!(
-            source.downcast_ref::<S3SelectPolicyError>(),
-            Some(S3SelectPolicyError::QueryTimeout { seconds: 300 })
+            source.downcast_ref::<SelectError>(),
+            Some(SelectError::QueryTimeout { seconds: 300 })
         ));
         assert_eq!(admission.available_permits(), 1);
         assert!(output.next().await.is_none());
@@ -2174,8 +2209,8 @@ mod tests {
             panic!("expected external query error");
         };
         assert!(matches!(
-            source.downcast_ref::<S3SelectPolicyError>(),
-            Some(S3SelectPolicyError::QueryTimeout { seconds: 1 })
+            source.downcast_ref::<SelectError>(),
+            Some(SelectError::QueryTimeout { seconds: 1 })
         ));
         assert_eq!(admission.available_permits(), 1);
         assert!(output.next().await.is_none());

crates/s3select-query/src/dispatcher/parquet_table.rs

@@ -38,7 +38,7 @@ use datafusion::{
 };
 use futures::{FutureExt, TryFutureExt, future::BoxFuture};
 use rustfs_s3select_api::{
-    QueryError, QueryResult,
+    QueryResult,
     object_store::{SelectScanRange, scan_range_from_bounds},
 };
 use s3s::dto::SelectObjectContentInput;
@@ -106,7 +106,10 @@ impl ParquetSelectTable {
         let object_store_url = table_path.object_store();
         let object_location = Path::from(input.key.clone());
         let store = state.runtime_env().object_store(&object_store_url)?;
-        let object_meta = store.head(&object_location).await.map_err(query_store_error)?;
+        let object_meta = store
+            .head(&object_location)
+            .await
+            .map_err(datafusion::common::DataFusionError::from)?;
 
         let reader = ObjectStoreParquetReader {
             store: Arc::clone(&store),
@@ -115,7 +118,7 @@ impl ParquetSelectTable {
         };
         let builder = ParquetRecordBatchStreamBuilder::new(reader)
             .await
-            .map_err(query_store_error)?;
+            .map_err(datafusion::common::DataFusionError::from)?;
         let schema = Arc::clone(builder.schema());
         let metadata = Arc::clone(builder.metadata());
         let access_plan = parquet_access_plan(input, object_meta.size, metadata.as_ref())?;
@@ -180,7 +183,8 @@ fn parquet_access_plan(
     let Some(scan_range) = input.request.scan_range.as_ref() else {
         return Ok(None);
     };
-    let scan_range = scan_range_from_bounds(scan_range.start, scan_range.end, object_size).map_err(query_store_error)?;
+    let scan_range = scan_range_from_bounds(scan_range.start, scan_range.end, object_size)
+        .map_err(datafusion::common::DataFusionError::from)?;
     Ok(scan_range.map(|range| Arc::new(access_plan_for_scan_range(range, metadata))))
 }
 
@@ -214,10 +218,6 @@ fn parquet_store_error(err: ObjectStoreError) -> ParquetError {
     ParquetError::External(Box::new(err))
 }
 
-fn query_store_error(err: impl fmt::Display) -> QueryError {
-    QueryError::StoreError { e: err.to_string() }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -227,7 +227,13 @@ mod tests {
             datatypes::{DataType, Field, Schema, SchemaRef},
             record_batch::RecordBatch,
         },
+        object_store::memory::InMemory,
         parquet::arrow::{ArrowWriter, arrow_reader::ParquetRecordBatchReaderBuilder},
+        prelude::SessionContext,
+    };
+    use rustfs_s3select_api::SelectError;
+    use s3s::dto::{
+        CSVOutput, ExpressionType, InputSerialization, OutputSerialization, ParquetInput, ScanRange, SelectObjectContentRequest,
     };
     use std::{
         fs::File,
@@ -275,6 +281,85 @@ mod tests {
         assert!(!plan.should_scan(1));
     }
 
+    #[test]
+    fn parquet_access_plan_has_typed_invalid_scan_range_error() {
+        let metadata = two_row_group_metadata();
+        let mut input = parquet_input("test.parquet");
+        input.request.scan_range = Some(ScanRange {
+            start: Some(10),
+            end: None,
+        });
+
+        let error = parquet_access_plan(&input, 10, metadata.as_ref()).expect_err("out-of-bounds range must fail");
+
+        assert_eq!(error.select_error(), SelectError::InvalidScanRange);
+    }
+
+    #[tokio::test]
+    async fn try_new_preserves_missing_object_error() {
+        let store = Arc::new(InMemory::new());
+        let context = parquet_session(store);
+        let state = context.state();
+
+        let error = match ParquetSelectTable::try_new(&state, &parquet_input("missing.parquet")).await {
+            Ok(_) => panic!("missing parquet object must fail"),
+            Err(error) => error,
+        };
+
+        assert_eq!(error.select_error(), SelectError::ObjectNotFound);
+    }
+
+    #[tokio::test]
+    async fn try_new_preserves_parquet_metadata_error() {
+        let store = Arc::new(InMemory::new());
+        let object = Path::from("corrupt.parquet");
+        store
+            .put(&object, Bytes::from_static(b"not a parquet file").into())
+            .await
+            .expect("put corrupt parquet object");
+        let context = parquet_session(store);
+        let state = context.state();
+
+        let error = match ParquetSelectTable::try_new(&state, &parquet_input(object.as_ref())).await {
+            Ok(_) => panic!("corrupt parquet metadata must fail"),
+            Err(error) => error,
+        };
+
+        assert_eq!(error.select_error(), SelectError::ParquetParsingError);
+    }
+
+    fn parquet_session(store: Arc<dyn ObjectStore>) -> SessionContext {
+        let context = SessionContext::new();
+        let store_url = ObjectStoreUrl::parse("s3://test-bucket").expect("valid test object store URL");
+        context.register_object_store(store_url.as_ref(), store);
+        context
+    }
+
+    fn parquet_input(key: &str) -> SelectObjectContentInput {
+        SelectObjectContentInput {
+            bucket: "test-bucket".to_string(),
+            expected_bucket_owner: None,
+            key: key.to_string(),
+            sse_customer_algorithm: None,
+            sse_customer_key: None,
+            sse_customer_key_md5: None,
+            request: SelectObjectContentRequest {
+                expression: "SELECT * FROM S3Object".to_string(),
+                expression_type: ExpressionType::from_static(ExpressionType::SQL),
+                input_serialization: InputSerialization {
+                    parquet: Some(ParquetInput::default()),
+                    ..Default::default()
+                },
+                output_serialization: OutputSerialization {
+                    csv: Some(CSVOutput::default()),
+                    ..Default::default()
+                },
+                request_progress: None,
+                scan_range: None,
+            },
+        }
+    }
+
     fn two_row_group_metadata() -> Arc<ParquetMetaData> {
         let now = SystemTime::now()
             .duration_since(UNIX_EPOCH)

crates/s3select-query/src/sql/planner.rs

@@ -23,7 +23,7 @@ use datafusion::sql::{
     },
 };
 use rustfs_s3select_api::{
-    QueryError, QueryResult, S3SelectPolicyError,
+    QueryError, QueryResult, SelectError,
     query::{
         ast::ExtStatement,
         logical_planner::{LogicalPlanner, Plan, QueryPlan},
@@ -68,7 +68,7 @@ impl<'a, S: ContextProviderExtension + Send + Sync + 'a> SqlPlanner<'a, S> {
         match stmt {
             Statement::Query(_) => {
                 validate_s3_select_statement(&stmt)?;
-                let df_plan = self.df_planner.sql_statement_to_plan(stmt)?;
+                let df_plan = self.df_planner.sql_statement_to_plan(stmt).map_err(classify_planner_error)?;
                 let plan = Plan::Query(QueryPlan {
                     df_plan,
                     is_tag_scan: false,
@@ -76,11 +76,25 @@ impl<'a, S: ContextProviderExtension + Send + Sync + 'a> SqlPlanner<'a, S> {
 
                 Ok(plan)
             }
-            _ => Err(QueryError::NotImplemented { err: stmt.to_string() }),
+            _ => Err(unsupported_structure("only SELECT queries are supported")),
         }
     }
 }
 
+fn classify_planner_error(error: datafusion::common::DataFusionError) -> QueryError {
+    if matches!(
+        &error,
+        datafusion::common::DataFusionError::Plan(message)
+            if message.starts_with("Failed to coerce arguments to satisfy a call to")
+                || (message.starts_with("Internal error: Function '")
+                    && message.contains("' failed to match any signature, errors:"))
+    ) {
+        return SelectError::IncorrectSqlFunctionArgumentType.into();
+    }
+
+    error.into()
+}
+
 fn validate_s3_select_statement(statement: &Statement) -> QueryResult<()> {
     let Statement::Query(query) = statement else {
         return Err(unsupported_structure("only SELECT queries are supported"));
@@ -191,7 +205,7 @@ fn validate_select(select: &Select) -> QueryResult<()> {
     let ([ObjectNamePart::Identifier(table_name)] | [ObjectNamePart::Identifier(table_name), ObjectNamePart::Identifier(_)]) =
         name.0.as_slice()
     else {
-        return Err(unsupported_structure("the source must be S3Object"));
+        return Err(SelectError::DataSourcePathUnsupported.into());
     };
     let is_s3_object = if table_name.quote_style.is_some() {
         table_name.value == "S3Object"
@@ -199,14 +213,14 @@ fn validate_select(select: &Select) -> QueryResult<()> {
         table_name.value.eq_ignore_ascii_case("S3Object")
     };
     if !is_s3_object {
-        return Err(unsupported_structure("the source must be S3Object"));
+        return Err(SelectError::DataSourcePathUnsupported.into());
     }
 
     Ok(())
 }
 
 fn unsupported_structure(message: &str) -> QueryError {
-    S3SelectPolicyError::UnsupportedSqlStructure {
+    SelectError::UnsupportedSqlStructure {
         message: message.to_string(),
     }
     .into()
@@ -234,7 +248,7 @@ mod tests {
     use super::validate_s3_select_statement;
     use crate::sql::parser::ExtParser;
     use datafusion::sql::sqlparser::ast::Statement;
-    use rustfs_s3select_api::{S3SelectPolicyError, query::ast::ExtStatement};
+    use rustfs_s3select_api::{SelectError, query::ast::ExtStatement};
 
     fn parse_statement(sql: &str) -> Statement {
         let mut statements = ExtParser::parse_sql(sql).expect("SQL should parse");
@@ -271,7 +285,7 @@ mod tests {
             validate_s3_select_statement(&statement),
             Err(ref err) if matches!(
                 err.s3_select_policy_error(),
-                Some(S3SelectPolicyError::UnsupportedSqlStructure { message }) if message == "JOIN is not supported"
+                Some(SelectError::UnsupportedSqlStructure { message }) if message == "JOIN is not supported"
             )
         ));
     }
@@ -284,7 +298,7 @@ mod tests {
             validate_s3_select_statement(&statement),
             Err(ref err) if matches!(
                 err.s3_select_policy_error(),
-                Some(S3SelectPolicyError::UnsupportedSqlStructure { message }) if message == "subqueries are not supported"
+                Some(SelectError::UnsupportedSqlStructure { message }) if message == "subqueries are not supported"
             )
         ));
     }
@@ -297,7 +311,7 @@ mod tests {
             validate_s3_select_statement(&statement),
             Err(ref err) if matches!(
                 err.s3_select_policy_error(),
-                Some(S3SelectPolicyError::UnsupportedSqlStructure { message }) if message == "subqueries are not supported"
+                Some(SelectError::UnsupportedSqlStructure { message }) if message == "subqueries are not supported"
             )
         ));
     }
@@ -310,7 +324,7 @@ mod tests {
             validate_s3_select_statement(&statement),
             Err(ref err) if matches!(
                 err.s3_select_policy_error(),
-                Some(S3SelectPolicyError::UnsupportedSqlStructure { message }) if message == "the source must be S3Object"
+                Some(SelectError::DataSourcePathUnsupported)
             )
         ));
     }
@@ -326,7 +340,7 @@ mod tests {
             assert!(
                 matches!(
                     validate_s3_select_statement(&statement),
-                    Err(ref err) if matches!(err.s3_select_policy_error(), Some(S3SelectPolicyError::UnsupportedSqlStructure { .. }))
+                    Err(ref err) if matches!(err.s3_select_policy_error(), Some(SelectError::UnsupportedSqlStructure { .. }))
                 ),
                 "query should be rejected: {sql}"
             );

crates/s3select-query/src/test/error_handling_test.rs

@@ -16,7 +16,7 @@
 mod error_handling_tests {
     use crate::get_global_db;
     use rustfs_s3select_api::{
-        QueryError,
+        QueryError, SelectError,
         query::{Context, Query},
     };
     use s3s::dto::{
@@ -98,7 +98,6 @@ mod error_handling_tests {
             "INSERT INTO S3Object VALUES (1, 'test')",
             "UPDATE S3Object SET name = 'test'",
             "DELETE FROM S3Object",
-            "CREATE TABLE test (id INT)",
             "DROP TABLE S3Object",
         ];
 
@@ -113,6 +112,68 @@ mod error_handling_tests {
         }
     }
 
+    #[tokio::test]
+    async fn test_non_select_statement_is_typed_unsupported_structure() {
+        let sql = "CREATE TABLE test (id INT)";
+        let input = create_test_input_with_sql(sql);
+        let db = get_global_db(input.clone(), true).await.unwrap();
+        let query = Query::new(Context { input: Arc::new(input) }, sql.to_string());
+
+        let error = match db.execute(&query).await {
+            Err(error) => error,
+            Ok(_) => panic!("non-SELECT statement must fail"),
+        };
+
+        assert!(matches!(error.select_error(), SelectError::UnsupportedSqlStructure { .. }));
+    }
+
+    #[tokio::test]
+    async fn test_function_argument_coercion_failure_is_typed() {
+        for sql in ["SELECT ROUND(3.14, 1.1) FROM S3Object", "SELECT SQRT(1, 2) FROM S3Object"] {
+            let input = create_test_input_with_sql(sql);
+            let db = get_global_db(input.clone(), true)
+                .await
+                .expect("test database should initialize");
+            let query = Query::new(Context { input: Arc::new(input) }, sql.to_string());
+
+            let error = match db.execute(&query).await {
+                Err(error) => error,
+                Ok(_) => panic!("invalid function arguments must fail during planning: {sql}"),
+            };
+
+            assert_eq!(
+                error.select_error(),
+                SelectError::IncorrectSqlFunctionArgumentType,
+                "unexpected planner error for {sql}: {error:?}"
+            );
+        }
+    }
+
+    #[tokio::test]
+    async fn test_other_planner_failures_remain_invalid_query() {
+        for sql in [
+            "SELECT DEFINITELY_UNKNOWN_FUNCTION(1) FROM S3Object",
+            "SELECT 1 + 'text' FROM S3Object",
+        ] {
+            let input = create_test_input_with_sql(sql);
+            let db = get_global_db(input.clone(), true)
+                .await
+                .expect("test database should initialize");
+            let query = Query::new(Context { input: Arc::new(input) }, sql.to_string());
+
+            let error = match db.execute(&query).await {
+                Err(error) => error,
+                Ok(_) => panic!("invalid query must fail during planning: {sql}"),
+            };
+
+            assert_eq!(
+                error.select_error(),
+                SelectError::InvalidQuery,
+                "unexpected planner error for {sql}: {error:?}"
+            );
+        }
+    }
+
     #[tokio::test]
     async fn test_invalid_column_references() {
         let invalid_column_sqls = vec![

rustfs/src/app/select_object.rs

@@ -15,12 +15,13 @@ use datafusion::arrow::{
     json::{WriterBuilder as JsonWriterBuilder, writer::LineDelimited},
     record_batch::RecordBatch,
 };
+#[cfg(test)]
 use datafusion::common::DataFusionError;
 use datafusion::physical_plan::SendableRecordBatchStream;
 use futures::StreamExt;
 use http::{HeaderMap, HeaderName, HeaderValue, StatusCode, header::RANGE};
 use rustfs_s3select_api::{
-    QueryError, S3SelectPolicyError,
+    QueryError, SelectError,
     object_store::{INVALID_SCAN_RANGE_MESSAGE, validate_scan_range_bounds},
     query::{Context, Query},
 };
@@ -49,8 +50,13 @@ use tracing::info;
 
 const MAX_SELECT_EXPRESSION_BYTES: usize = 256 * 1024;
 const RECORDS_CHUNK_TARGET: usize = 128 * 1024;
+const DATA_SOURCE_PATH_UNSUPPORTED_CODE: &str = "DataSourcePathUnsupported";
+const INVALID_QUERY_CODE: &str = "InvalidQuery";
 const PARSE_SELECT_FAILURE_CODE: &str = "ParseSelectFailure";
+const BUSY_MESSAGE: &str = "The service is unavailable. Try again later.";
 const EMPTY_SELECT_EXPRESSION_MESSAGE: &str = "empty SQL expression";
+const SLOW_DOWN_MESSAGE: &str = "Reduce your request rate.";
+const UNSUPPORTED_SQL_STRUCTURE_MESSAGE: &str = "We encountered an unsupported SQL structure. Check the SQL Reference.";
 const SELECT_MINIO_SSEC_SEALED_KEY: &str = "X-Minio-Internal-Server-Side-Encryption-Sealed-Key";
 const SELECT_MINIO_S3_SEALED_KEY: &str = "X-Minio-Internal-Server-Side-Encryption-S3-Sealed-Key";
 const SELECT_MINIO_KMS_SEALED_KEY: &str = "X-Minio-Internal-Server-Side-Encryption-Kms-Sealed-Key";
@@ -82,12 +88,7 @@ trait SelectSnapshotFence {
 
 impl SelectSnapshotFence for Arc<StorageSelectObjectSnapshot> {
     fn ensure_snapshot_valid(&self) -> S3Result<()> {
-        self.ensure_valid().map_err(|error| {
-            let message = error.to_string();
-            let mut s3_error = S3Error::with_message(S3ErrorCode::InternalError, message);
-            s3_error.set_source(Box::new(error));
-            s3_error
-        })
+        self.ensure_valid().map_err(internal_select_error)
     }
 }
 
@@ -128,7 +129,7 @@ pub async fn execute_select_object_content(
     let terminal_permit = tx
         .clone()
         .try_reserve_owned()
-        .map_err(|_| s3_error!(InternalError, "can't reserve Select terminal event capacity"))?;
+        .map_err(|_| map_select_error_to_s3(&SelectError::InternalError))?;
     let response = select_object_response(rx, &snapshot.object_info().user_defined, &req.headers)?;
     spawn_traced(async move {
         send_select_events_until_deadline(
@@ -338,7 +339,7 @@ async fn send_select_events_until_deadline<L: SelectSnapshotFence>(
     let outcome = match timeout_at(deadline, send_select_events(output, &tx, validation, &snapshot_lease)).await {
         Ok(outcome) => outcome,
         Err(_) => SelectProducerOutcome::Terminal(Err(map_query_error_to_s3(
-            S3SelectPolicyError::QueryTimeout {
+            SelectError::QueryTimeout {
                 seconds: timeout_seconds,
             }
             .into(),
@@ -416,12 +417,14 @@ async fn send_select_events(
     let stats = SelectObjectContentEvent::Stats(StatsEvent {
         details: Some(progress.to_stats()),
     });
-    if tx.send(Ok(stats)).await.is_err() {
-        return SelectProducerOutcome::ReceiverClosed;
-    }
+    let stats_permit = match tx.reserve().await {
+        Ok(permit) => permit,
+        Err(_) => return SelectProducerOutcome::ReceiverClosed,
+    };
     if let Err(error) = snapshot_fence.ensure_snapshot_valid() {
         return SelectProducerOutcome::Terminal(Err(error));
     }
+    stats_permit.send(Ok(stats));
     SelectProducerOutcome::Terminal(Ok(SelectObjectContentEvent::End(EndEvent::default())))
 }
 
@@ -441,7 +444,9 @@ fn validate_select_request(headers: &http::HeaderMap, input: &mut SelectObjectCo
 
     let output_format = normalize_output_serialization(&mut input.request.output_serialization)?;
     if input.request.expression.trim().is_empty() {
-        return Err(parse_select_failure(EMPTY_SELECT_EXPRESSION_MESSAGE));
+        return Err(map_select_error_to_s3(&SelectError::ParseSelectFailure {
+            message: EMPTY_SELECT_EXPRESSION_MESSAGE.to_string(),
+        }));
     }
     let progress_enabled = input
         .request
@@ -466,13 +471,17 @@ fn normalize_input_serialization(input: &mut InputSerialization) -> S3Result<()>
         return Err(S3Error::new(S3ErrorCode::ObjectSerializationConflict));
     }
 
-    if let Some(compression) = input.compression_type.as_ref()
-        && compression.as_str() != CompressionType::NONE
-    {
-        return Err(s3_error!(
-            NotImplemented,
-            "SelectObjectContent currently supports only uncompressed input"
-        ));
+    if let Some(compression) = input.compression_type.as_ref() {
+        match compression.as_str() {
+            CompressionType::NONE => {}
+            CompressionType::GZIP | CompressionType::BZIP2 => {
+                return Err(s3_error!(
+                    NotImplemented,
+                    "SelectObjectContent currently supports only uncompressed input"
+                ));
+            }
+            _ => return Err(map_select_error_to_s3(&SelectError::InvalidCompressionFormat)),
+        }
     }
     input.compression_type = Some(CompressionType::from_static(CompressionType::NONE));
 
@@ -483,8 +492,18 @@ fn normalize_input_serialization(input: &mut InputSerialization) -> S3Result<()>
                 "CSV AllowQuotedRecordDelimiter is not supported by SelectObjectContent"
             ));
         }
-        csv.file_header_info
+        let file_header_info = csv
+            .file_header_info
             .get_or_insert_with(|| FileHeaderInfo::from_static(FileHeaderInfo::NONE));
+        if !matches!(
+            file_header_info.as_str(),
+            FileHeaderInfo::NONE | FileHeaderInfo::USE | FileHeaderInfo::IGNORE
+        ) {
+            return Err(S3Error::with_message(
+                S3ErrorCode::InvalidFileHeaderInfo,
+                "The FileHeaderInfo value is not valid. Only NONE, USE, and IGNORE are supported.",
+            ));
+        }
         validate_single_byte(csv.comments.as_deref(), S3ErrorCode::InvalidRequestParameter)?;
         validate_single_byte(csv.quote_character.as_deref(), S3ErrorCode::InvalidRequestParameter)?;
         validate_single_byte(csv.quote_escape_character.as_deref(), S3ErrorCode::InvalidRequestParameter)?;
@@ -575,12 +594,6 @@ fn invalid_scan_range_error() -> S3Error {
     S3Error::with_message(S3ErrorCode::InvalidRequestParameter, INVALID_SCAN_RANGE_MESSAGE.to_string())
 }
 
-fn parse_select_failure(message: impl Into<String>) -> S3Error {
-    let mut err = S3Error::with_message(S3ErrorCode::Custom(PARSE_SELECT_FAILURE_CODE.into()), message.into());
-    err.set_status_code(StatusCode::BAD_REQUEST);
-    err
-}
-
 fn validate_single_byte(value: Option<&str>, code: S3ErrorCode) -> S3Result<()> {
     if let Some(value) = value
         && value.len() != 1
@@ -646,12 +659,14 @@ async fn prepare_select_object_snapshot(
 
 fn map_prepare_snapshot_error(err: StoragePrepareSelectObjectSnapshotError) -> S3Error {
     match err {
-        StoragePrepareSelectObjectSnapshotError::Storage(err) => ApiError::from(err).into(),
-        err => {
-            let mut s3_error = S3Error::with_message(S3ErrorCode::InternalError, err.to_string());
-            s3_error.set_source(Box::new(err));
+        StoragePrepareSelectObjectSnapshotError::Storage(err) => {
+            let mut s3_error: S3Error = ApiError::from(err).into();
+            if s3_error.code() == &S3ErrorCode::InternalError {
+                s3_error.set_message(SelectError::InternalError.to_string());
+            }
             s3_error
         }
+        err => internal_select_error(err),
     }
 }
 
@@ -719,9 +734,7 @@ fn encode_csv_batch(batch: &RecordBatch, config: &CSVOutput) -> S3Result<Vec<u8>
     }
 
     let mut writer = builder.build(&mut buffer);
-    writer
-        .write(batch)
-        .map_err(|err| s3_error!(InternalError, "can't encode Select output to CSV: {}", err))?;
+    writer.write(batch).map_err(internal_select_error)?;
     drop(writer);
     Ok(buffer)
 }
@@ -739,12 +752,8 @@ fn encode_json_batch(batch: &RecordBatch, config: &JSONOutput) -> S3Result<Vec<u
     let mut writer = JsonWriterBuilder::new()
         .with_explicit_nulls(true)
         .build::<_, LineDelimited>(&mut buffer);
-    writer
-        .write(batch)
-        .map_err(|err| s3_error!(InternalError, "can't encode Select output to JSON: {}", err))?;
-    writer
-        .finish()
-        .map_err(|err| s3_error!(InternalError, "can't finish Select JSON output: {}", err))?;
+    writer.write(batch).map_err(internal_select_error)?;
+    writer.finish().map_err(internal_select_error)?;
     drop(writer);
 
     if let Some(delimiter) = config.record_delimiter.as_deref()
@@ -813,122 +822,60 @@ fn clamp_i64(value: u64) -> i64 {
 }
 
 fn map_query_error_to_s3(err: QueryError) -> S3Error {
-    if err.is_snapshot_consistency_error() {
-        let message = err.to_string();
-        let mut s3_error = S3Error::with_message(S3ErrorCode::InternalError, message);
-        s3_error.set_source(Box::new(err));
-        return s3_error;
-    }
-    if let Some(policy_error) = err.s3_select_policy_error() {
-        let message = policy_error.to_string();
-        return match policy_error {
-            S3SelectPolicyError::UnsupportedSqlStructure { .. } => {
-                S3Error::with_message(S3ErrorCode::UnsupportedSqlStructure, message)
-            }
-            S3SelectPolicyError::QueryConcurrencyLimit => S3Error::with_message(S3ErrorCode::SlowDown, message),
-            S3SelectPolicyError::QueryTimeout { .. } => S3Error::with_message(S3ErrorCode::Busy, message),
-            _ => S3Error::with_message(S3ErrorCode::InternalError, message),
-        };
-    }
-    let message = err.to_string();
+    let select_error = err.select_error();
+    map_select_error_to_s3(&select_error)
+}
+
+fn map_select_error_to_s3(err: &SelectError) -> S3Error {
     match err {
-        QueryError::Parser { .. } => parse_select_failure(message),
-        QueryError::MultiStatement { .. } => S3Error::with_message(S3ErrorCode::UnsupportedSqlStructure, message),
-        QueryError::NotImplemented { .. } => S3Error::with_message(S3ErrorCode::NotImplemented, message),
-        QueryError::Datafusion { source } if is_resource_exhausted(source.as_ref()) => {
-            S3Error::with_message(S3ErrorCode::Busy, message)
+        SelectError::InvalidCompressionFormat => S3Error::with_message(S3ErrorCode::InvalidCompressionFormat, err.to_string()),
+        SelectError::InvalidDataSource => S3Error::with_message(S3ErrorCode::InvalidDataSource, err.to_string()),
+        SelectError::TruncatedInput => S3Error::with_message(S3ErrorCode::TruncatedInput, err.to_string()),
+        SelectError::CsvParsingError => S3Error::with_message(S3ErrorCode::CSVParsingError, err.to_string()),
+        SelectError::JsonParsingError => S3Error::with_message(S3ErrorCode::JSONParsingError, err.to_string()),
+        SelectError::ParquetParsingError => S3Error::with_message(S3ErrorCode::ParquetParsingError, err.to_string()),
+        SelectError::ParseSelectFailure { message } => custom_bad_request(PARSE_SELECT_FAILURE_CODE, message.clone()),
+        SelectError::InvalidQuery => custom_bad_request(INVALID_QUERY_CODE, err.to_string()),
+        SelectError::InvalidDataType => S3Error::with_message(S3ErrorCode::InvalidDataType, err.to_string()),
+        SelectError::IncorrectSqlFunctionArgumentType => {
+            S3Error::with_message(S3ErrorCode::IncorrectSqlFunctionArgumentType, err.to_string())
         }
-        QueryError::Datafusion { source } if is_unexpected_eof(source.as_ref()) => {
-            S3Error::with_message(S3ErrorCode::InternalError, message)
+        SelectError::DataSourcePathUnsupported => custom_bad_request(DATA_SOURCE_PATH_UNSUPPORTED_CODE, err.to_string()),
+        SelectError::UnsupportedSqlStructure { .. } => {
+            S3Error::with_message(S3ErrorCode::UnsupportedSqlStructure, UNSUPPORTED_SQL_STRUCTURE_MESSAGE)
         }
-        QueryError::Datafusion { source } if is_invalid_object_size(source.as_ref()) => {
-            S3Error::with_message(S3ErrorCode::InternalError, message)
+        SelectError::UnsupportedSqlOperation => S3Error::with_message(S3ErrorCode::UnsupportedSqlOperation, err.to_string()),
+        SelectError::EvaluatorBindingDoesNotExist => {
+            S3Error::with_message(S3ErrorCode::EvaluatorBindingDoesNotExist, err.to_string())
         }
-        QueryError::Datafusion { .. } if looks_like_invalid_scan_range(&message) => {
+        SelectError::AmbiguousFieldName => S3Error::with_message(S3ErrorCode::AmbiguousFieldName, err.to_string()),
+        SelectError::InvalidScanRange => {
             S3Error::with_message(S3ErrorCode::InvalidRequestParameter, INVALID_SCAN_RANGE_MESSAGE.to_string())
         }
-        QueryError::Datafusion { .. } if looks_like_missing_binding(&message) => {
-            S3Error::with_message(S3ErrorCode::EvaluatorBindingDoesNotExist, message)
+        SelectError::QueryConcurrencyLimit => S3Error::with_message(S3ErrorCode::SlowDown, SLOW_DOWN_MESSAGE),
+        SelectError::QueryTimeout { .. } | SelectError::ResourceExhausted => {
+            S3Error::with_message(S3ErrorCode::Busy, BUSY_MESSAGE)
         }
-        QueryError::Datafusion { .. } => S3Error::with_message(S3ErrorCode::UnsupportedSqlOperation, message),
-        QueryError::StoreError { .. } if looks_like_invalid_scan_range(&message) => {
-            S3Error::with_message(S3ErrorCode::InvalidRequestParameter, INVALID_SCAN_RANGE_MESSAGE.to_string())
+        SelectError::BucketNotFound => S3Error::with_message(S3ErrorCode::NoSuchBucket, err.to_string()),
+        SelectError::ObjectNotFound => S3Error::with_message(S3ErrorCode::NoSuchKey, err.to_string()),
+        SelectError::Canceled | SelectError::InternalError => {
+            S3Error::with_message(S3ErrorCode::InternalError, SelectError::InternalError.to_string())
         }
-        QueryError::StoreError { .. } if looks_like_bucket_not_found(&message) => {
-            S3Error::with_message(S3ErrorCode::NoSuchBucket, message)
-        }
-        QueryError::StoreError { .. } if looks_like_object_not_found(&message) => {
-            S3Error::with_message(S3ErrorCode::NoSuchKey, message)
-        }
-        QueryError::StoreError { .. } => S3Error::with_message(S3ErrorCode::InternalError, message),
-        QueryError::BuildQueryDispatcher { .. }
-        | QueryError::Cancel
-        | QueryError::FunctionNotExists { .. }
-        | QueryError::FunctionExists { .. } => S3Error::with_message(S3ErrorCode::InternalError, message),
     }
 }
 
+fn internal_select_error(_error: impl std::error::Error + Send + Sync + 'static) -> S3Error {
+    map_select_error_to_s3(&SelectError::InternalError)
+}
+
+fn custom_bad_request(code: &'static str, message: String) -> S3Error {
+    let mut err = S3Error::with_message(S3ErrorCode::Custom(code.into()), message);
+    err.set_status_code(StatusCode::BAD_REQUEST);
+    err
+}
+
 fn select_query_timeout_error(seconds: u64) -> S3Error {
-    map_query_error_to_s3(S3SelectPolicyError::QueryTimeout { seconds }.into())
-}
-
-fn looks_like_bucket_not_found(message: &str) -> bool {
-    message.contains("NoSuchBucket") || message.contains("bucket not found") || message.contains("BucketNotFound")
-}
-
-const MAX_ERROR_SOURCE_DEPTH: usize = 16;
-
-fn error_chain_any(
-    mut err: &(dyn std::error::Error + 'static),
-    predicate: impl Fn(&(dyn std::error::Error + 'static)) -> bool,
-) -> bool {
-    for _ in 0..MAX_ERROR_SOURCE_DEPTH {
-        if predicate(err) {
-            return true;
-        }
-        let Some(source) = err.source() else {
-            return false;
-        };
-        err = source;
-    }
-    false
-}
-
-fn is_resource_exhausted(err: &(dyn std::error::Error + 'static)) -> bool {
-    error_chain_any(err, |err| {
-        err.downcast_ref::<DataFusionError>()
-            .is_some_and(|err| matches!(err, DataFusionError::ResourcesExhausted(_)))
-    })
-}
-
-fn is_unexpected_eof(err: &(dyn std::error::Error + 'static)) -> bool {
-    error_chain_any(err, |err| {
-        err.downcast_ref::<std::io::Error>()
-            .is_some_and(|err| err.kind() == std::io::ErrorKind::UnexpectedEof)
-    })
-}
-
-fn is_invalid_object_size(err: &(dyn std::error::Error + 'static)) -> bool {
-    error_chain_any(err, |err| err.downcast_ref::<std::num::TryFromIntError>().is_some())
-}
-
-fn looks_like_object_not_found(message: &str) -> bool {
-    message.contains("NoSuchKey")
-        || message.contains("NoSuchVersion")
-        || message.contains("ObjectNotFound")
-        || message.contains("object not found")
-        || message.contains("NotFound")
-}
-
-fn looks_like_missing_binding(message: &str) -> bool {
-    message.contains("No field named")
-        || message.contains("field not found")
-        || message.contains("Schema error")
-        || message.contains("No such column")
-}
-
-fn looks_like_invalid_scan_range(message: &str) -> bool {
-    message.contains("ScanRange:") || message.contains(INVALID_SCAN_RANGE_MESSAGE)
+    map_query_error_to_s3(SelectError::QueryTimeout { seconds }.into())
 }
 
 fn is_json_document(json: &JSONInput) -> bool {
@@ -942,8 +889,9 @@ mod tests {
     use super::*;
     use datafusion::{
         arrow::{
-            array::{Array, ListArray},
-            datatypes::{Field, Int32Type, Schema},
+            array::{Array, ListArray, StringArray},
+            datatypes::{DataType, Field, Int32Type, Schema},
+            error::ArrowError,
         },
         physical_plan::stream::RecordBatchStreamAdapter,
         sql::sqlparser::parser::ParserError,
@@ -951,6 +899,53 @@ mod tests {
     use rustfs_test_utils::TestECStoreEnv;
     use s3s::dto::{CSVInput, ParquetInput, ScanRange};
 
+    fn event_stream_headers(mut bytes: &[u8]) -> Vec<Vec<(String, String)>> {
+        let mut messages = Vec::new();
+        while !bytes.is_empty() {
+            assert!(bytes.len() >= 16, "event-stream message is truncated");
+            let total_len = u32::from_be_bytes(bytes[0..4].try_into().expect("event-stream total length")) as usize;
+            let headers_len = u32::from_be_bytes(bytes[4..8].try_into().expect("event-stream headers length")) as usize;
+            assert!(total_len >= 16 && total_len <= bytes.len(), "invalid event-stream message length");
+            assert!(12 + headers_len <= total_len - 4, "invalid event-stream headers length");
+
+            let mut headers = &bytes[12..12 + headers_len];
+            let mut decoded = Vec::new();
+            while !headers.is_empty() {
+                let name_len = headers[0] as usize;
+                assert!(headers.len() >= name_len + 4, "event-stream header is truncated");
+                let name = std::str::from_utf8(&headers[1..1 + name_len])
+                    .expect("event-stream header name should be UTF-8")
+                    .to_string();
+                assert_eq!(headers[1 + name_len], 7, "expected an event-stream string header");
+                let value_len = u16::from_be_bytes(
+                    headers[2 + name_len..4 + name_len]
+                        .try_into()
+                        .expect("event-stream header value length"),
+                ) as usize;
+                assert!(headers.len() >= name_len + 4 + value_len, "event-stream header value is truncated");
+                let value = std::str::from_utf8(&headers[4 + name_len..4 + name_len + value_len])
+                    .expect("event-stream header value should be UTF-8")
+                    .to_string();
+                decoded.push((name, value));
+                headers = &headers[4 + name_len + value_len..];
+            }
+            messages.push(decoded);
+            bytes = &bytes[total_len..];
+        }
+        messages
+    }
+
+    async fn http_xml_error(error: S3Error) -> (StatusCode, String) {
+        let response = error.to_http_response().expect("S3 error should serialize to HTTP");
+        let status = response.status();
+        let body = http_body_util::BodyExt::collect(response.into_body())
+            .await
+            .expect("S3 error body should be readable")
+            .to_bytes();
+        let body = std::str::from_utf8(&body).expect("S3 error XML should be UTF-8").to_string();
+        (status, body)
+    }
+
     struct LeaseDropSignal(Option<tokio::sync::oneshot::Sender<()>>);
 
     impl Drop for LeaseDropSignal {
@@ -1010,22 +1005,8 @@ mod tests {
             .expect_err("production fence adapter must reject a lost storage snapshot");
 
         assert_eq!(error.code(), &S3ErrorCode::InternalError);
-        assert!(error.to_string().contains("namespace lock was lost"));
-    }
-
-    #[derive(Debug)]
-    struct CyclicError;
-
-    impl std::fmt::Display for CyclicError {
-        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-            f.write_str("cyclic error")
-        }
-    }
-
-    impl std::error::Error for CyclicError {
-        fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
-            Some(self)
-        }
+        assert_eq!(error.message(), Some("An internal error occurred."));
+        assert!(error.source().is_none());
     }
 
     fn base_input() -> SelectObjectContentInput {
@@ -1272,15 +1253,15 @@ mod tests {
     #[test]
     fn map_query_policy_errors_to_s3_errors() {
         let unsupported = map_query_error_to_s3(
-            S3SelectPolicyError::UnsupportedSqlStructure {
+            SelectError::UnsupportedSqlStructure {
                 message: "JOIN is not supported".to_string(),
             }
             .into(),
         );
-        let saturated = map_query_error_to_s3(S3SelectPolicyError::QueryConcurrencyLimit.into());
-        let timed_out = map_query_error_to_s3(S3SelectPolicyError::QueryTimeout { seconds: 300 }.into());
+        let saturated = map_query_error_to_s3(SelectError::QueryConcurrencyLimit.into());
+        let timed_out = map_query_error_to_s3(SelectError::QueryTimeout { seconds: 300 }.into());
         let stream_timed_out = map_query_error_to_s3(QueryError::Datafusion {
-            source: Box::new(DataFusionError::External(Box::new(S3SelectPolicyError::QueryTimeout { seconds: 300 }))),
+            source: Box::new(DataFusionError::External(Box::new(SelectError::QueryTimeout { seconds: 300 }))),
         });
         let exhausted = map_query_error_to_s3(QueryError::Datafusion {
             source: Box::new(DataFusionError::ObjectStore(Box::new(datafusion::object_store::Error::Generic {
@@ -1289,6 +1270,9 @@ mod tests {
             }))),
         });
         let truncated = map_query_error_to_s3(QueryError::Datafusion {
+            source: Box::new(DataFusionError::External(Box::new(SelectError::TruncatedInput))),
+        });
+        let raw_storage_short_read = map_query_error_to_s3(QueryError::Datafusion {
             source: Box::new(DataFusionError::ObjectStore(Box::new(datafusion::object_store::Error::Generic {
                 store: "EcObjectStore",
                 source: Box::new(std::io::Error::new(std::io::ErrorKind::UnexpectedEof, "truncated object stream")),
@@ -1302,19 +1286,114 @@ mod tests {
         });
 
         assert_eq!(unsupported.code(), &S3ErrorCode::UnsupportedSqlStructure);
-        assert_eq!(unsupported.message(), Some("Unsupported S3 Select SQL structure: JOIN is not supported"));
+        assert_eq!(unsupported.message(), Some(UNSUPPORTED_SQL_STRUCTURE_MESSAGE));
         assert_eq!(saturated.code(), &S3ErrorCode::SlowDown);
-        assert_eq!(saturated.message(), Some("S3 Select query concurrency limit reached"));
         assert_eq!(timed_out.code(), &S3ErrorCode::Busy);
-        assert_eq!(timed_out.message(), Some("S3 Select query exceeded the 300-second execution limit"));
         assert_eq!(stream_timed_out.code(), &S3ErrorCode::Busy);
-        assert_eq!(
-            stream_timed_out.message(),
-            Some("S3 Select query exceeded the 300-second execution limit")
-        );
         assert_eq!(exhausted.code(), &S3ErrorCode::Busy);
-        assert_eq!(truncated.code(), &S3ErrorCode::InternalError);
+        assert_eq!(truncated.code(), &S3ErrorCode::TruncatedInput);
+        assert_eq!(raw_storage_short_read.code(), &S3ErrorCode::InternalError);
         assert_eq!(invalid_object_size.code(), &S3ErrorCode::InternalError);
+        assert_eq!(invalid_object_size.message(), Some("An internal error occurred."));
+    }
+
+    #[test]
+    fn every_select_error_has_an_explicit_protocol_mapping() {
+        let cases = vec![
+            (
+                SelectError::InvalidCompressionFormat,
+                S3ErrorCode::InvalidCompressionFormat,
+                StatusCode::BAD_REQUEST,
+            ),
+            (SelectError::InvalidDataSource, S3ErrorCode::InvalidDataSource, StatusCode::BAD_REQUEST),
+            (SelectError::TruncatedInput, S3ErrorCode::TruncatedInput, StatusCode::BAD_REQUEST),
+            (SelectError::CsvParsingError, S3ErrorCode::CSVParsingError, StatusCode::BAD_REQUEST),
+            (SelectError::JsonParsingError, S3ErrorCode::JSONParsingError, StatusCode::BAD_REQUEST),
+            (
+                SelectError::ParquetParsingError,
+                S3ErrorCode::ParquetParsingError,
+                StatusCode::BAD_REQUEST,
+            ),
+            (
+                SelectError::ParseSelectFailure {
+                    message: "invalid SELECT expression".to_string(),
+                },
+                S3ErrorCode::Custom(PARSE_SELECT_FAILURE_CODE.into()),
+                StatusCode::BAD_REQUEST,
+            ),
+            (
+                SelectError::InvalidQuery,
+                S3ErrorCode::Custom(INVALID_QUERY_CODE.into()),
+                StatusCode::BAD_REQUEST,
+            ),
+            (SelectError::InvalidDataType, S3ErrorCode::InvalidDataType, StatusCode::BAD_REQUEST),
+            (
+                SelectError::IncorrectSqlFunctionArgumentType,
+                S3ErrorCode::IncorrectSqlFunctionArgumentType,
+                StatusCode::BAD_REQUEST,
+            ),
+            (
+                SelectError::DataSourcePathUnsupported,
+                S3ErrorCode::Custom(DATA_SOURCE_PATH_UNSUPPORTED_CODE.into()),
+                StatusCode::BAD_REQUEST,
+            ),
+            (
+                SelectError::UnsupportedSqlStructure {
+                    message: "JOIN is not supported".to_string(),
+                },
+                S3ErrorCode::UnsupportedSqlStructure,
+                StatusCode::BAD_REQUEST,
+            ),
+            (
+                SelectError::UnsupportedSqlOperation,
+                S3ErrorCode::UnsupportedSqlOperation,
+                StatusCode::BAD_REQUEST,
+            ),
+            (
+                SelectError::EvaluatorBindingDoesNotExist,
+                S3ErrorCode::EvaluatorBindingDoesNotExist,
+                StatusCode::BAD_REQUEST,
+            ),
+            (SelectError::AmbiguousFieldName, S3ErrorCode::AmbiguousFieldName, StatusCode::BAD_REQUEST),
+            (
+                SelectError::InvalidScanRange,
+                S3ErrorCode::InvalidRequestParameter,
+                StatusCode::BAD_REQUEST,
+            ),
+            (SelectError::QueryConcurrencyLimit, S3ErrorCode::SlowDown, StatusCode::SERVICE_UNAVAILABLE),
+            (
+                SelectError::QueryTimeout { seconds: 300 },
+                S3ErrorCode::Busy,
+                StatusCode::SERVICE_UNAVAILABLE,
+            ),
+            (SelectError::ResourceExhausted, S3ErrorCode::Busy, StatusCode::SERVICE_UNAVAILABLE),
+            (SelectError::BucketNotFound, S3ErrorCode::NoSuchBucket, StatusCode::NOT_FOUND),
+            (SelectError::ObjectNotFound, S3ErrorCode::NoSuchKey, StatusCode::NOT_FOUND),
+            (SelectError::Canceled, S3ErrorCode::InternalError, StatusCode::INTERNAL_SERVER_ERROR),
+            (SelectError::InternalError, S3ErrorCode::InternalError, StatusCode::INTERNAL_SERVER_ERROR),
+        ];
+
+        for (select_error, expected_code, expected_status) in cases {
+            let error = map_select_error_to_s3(&select_error);
+            assert_eq!(error.code(), &expected_code, "wrong mapping for {select_error:?}");
+            assert_eq!(error.status_code(), Some(expected_status), "wrong status for {select_error:?}");
+            assert!(
+                error.message().is_some_and(|message| !message.is_empty()),
+                "missing protocol message for {select_error:?}"
+            );
+        }
+    }
+
+    #[test]
+    fn internal_query_details_are_not_exposed_to_clients() {
+        let private_detail = "node-1:/private/object/path physical_plan=secret";
+        let error = map_query_error_to_s3(QueryError::from(DataFusionError::Internal(private_detail.to_string())));
+
+        assert_eq!(error.code(), &S3ErrorCode::InternalError);
+        assert_eq!(error.message(), Some("An internal error occurred."));
+        assert!(!error.message().is_some_and(|message| message.contains(private_detail)));
+        assert!(!format!("{error:?}").contains(private_detail));
+        assert!(error.source().is_none());
     }
 
     #[test]
@@ -1329,23 +1408,12 @@ mod tests {
     }
 
     #[test]
-    fn prepare_snapshot_invalid_logical_size_fails_with_internal_error_and_source() {
+    fn prepare_snapshot_invalid_logical_size_fails_with_redacted_internal_error() {
         let err = map_prepare_snapshot_error(StoragePrepareSelectObjectSnapshotError::InvalidLogicalSize { size: -1 });
 
         assert_eq!(err.code(), &S3ErrorCode::InternalError);
-        assert!(
-            err.source()
-                .is_some_and(|source| source.downcast_ref::<StoragePrepareSelectObjectSnapshotError>().is_some())
-        );
-    }
-
-    #[test]
-    fn error_source_matching_stops_at_the_depth_bound() {
-        let err = CyclicError;
-
-        assert!(!is_resource_exhausted(&err));
-        assert!(!is_unexpected_eof(&err));
-        assert!(!is_invalid_object_size(&err));
+        assert!(err.source().is_none());
+        assert_eq!(err.message(), Some("An internal error occurred."));
     }
 
     #[tokio::test(start_paused = true)]
@@ -1422,6 +1490,39 @@ mod tests {
         assert!(lease_released.await.is_ok(), "End should release the snapshot lease");
     }
 
+    #[tokio::test(start_paused = true)]
+    async fn successful_stream_serializes_records_stats_and_end_without_error() {
+        let schema = Arc::new(Schema::new(vec![Field::new("value", DataType::Utf8, false)]));
+        let batch = RecordBatch::try_new(schema.clone(), vec![Arc::new(StringArray::from(vec!["row"]))])
+            .expect("test record batch should be valid");
+        let output = Box::pin(RecordBatchStreamAdapter::new(
+            schema,
+            futures::stream::once(async move { Ok::<_, DataFusionError>(batch) }),
+        ));
+        let (producer, rx, lease_released) = spawn_test_producer(output, 4);
+        producer.await.expect("producer should finish successfully");
+
+        let mut byte_stream = SelectObjectContentEventStream::new(ReceiverStream::new(rx)).into_byte_stream();
+        let mut encoded = Vec::new();
+        while let Some(chunk) = byte_stream.next().await {
+            encoded.extend_from_slice(&chunk.expect("event-stream message should serialize"));
+        }
+        let messages = event_stream_headers(&encoded);
+        let event_types = messages
+            .iter()
+            .filter_map(|headers| {
+                headers
+                    .iter()
+                    .find_map(|(name, value)| (name == ":event-type").then_some(value.as_str()))
+            })
+            .collect::<Vec<_>>();
+        assert_eq!(event_types, ["Cont", "Records", "Stats", "End"]);
+        assert!(!messages.iter().flatten().any(|(name, value)| {
+            (name == ":message-type" && value == "error") || name == ":error-code" || name == ":error-message"
+        }));
+        assert!(lease_released.await.is_ok(), "End should release the snapshot lease");
+    }
+
     #[tokio::test(start_paused = true)]
     async fn eof_at_deadline_uses_reserved_slot_for_stats_then_end() {
         let output = Box::pin(RecordBatchStreamAdapter::new(
@@ -1455,7 +1556,7 @@ mod tests {
             Arc::new(Schema::empty()),
             futures::stream::once(async {
                 tokio::time::sleep(std::time::Duration::from_secs(1)).await;
-                Err(DataFusionError::External(Box::new(S3SelectPolicyError::QueryConcurrencyLimit)))
+                Err(DataFusionError::External(Box::new(SelectError::QueryConcurrencyLimit)))
             }),
         ));
         let (producer, mut rx, lease_released) = spawn_test_producer(output, 2);
@@ -1475,6 +1576,172 @@ mod tests {
         assert!(lease_released.await.is_ok(), "stream error should release the snapshot lease");
     }
 
+    #[tokio::test(start_paused = true)]
+    async fn select_errors_use_http_codes_before_stream_and_error_frames_after_stream() {
+        fn csv_error() -> DataFusionError {
+            DataFusionError::ArrowError(Box::new(ArrowError::CsvError("private CSV parser state".to_string())), None)
+        }
+        fn json_error() -> DataFusionError {
+            DataFusionError::ArrowError(Box::new(ArrowError::JsonError("private JSON parser state".to_string())), None)
+        }
+        fn parquet_error() -> DataFusionError {
+            DataFusionError::ParquetError(Box::new(datafusion::parquet::errors::ParquetError::General(
+                "private Parquet parser state".to_string(),
+            )))
+        }
+        fn truncated_error() -> DataFusionError {
+            DataFusionError::External(Box::new(SelectError::TruncatedInput))
+        }
+        fn timeout_error() -> DataFusionError {
+            DataFusionError::External(Box::new(SelectError::QueryTimeout { seconds: 300 }))
+        }
+
+        let cases = [
+            (
+                csv_error as fn() -> DataFusionError,
+                S3ErrorCode::CSVParsingError,
+                StatusCode::BAD_REQUEST,
+                b"CSVParsingError" as &[u8],
+            ),
+            (json_error, S3ErrorCode::JSONParsingError, StatusCode::BAD_REQUEST, b"JSONParsingError"),
+            (
+                parquet_error,
+                S3ErrorCode::ParquetParsingError,
+                StatusCode::BAD_REQUEST,
+                b"ParquetParsingError",
+            ),
+            (truncated_error, S3ErrorCode::TruncatedInput, StatusCode::BAD_REQUEST, b"TruncatedInput"),
+            (timeout_error, S3ErrorCode::Busy, StatusCode::SERVICE_UNAVAILABLE, b"Busy"),
+        ];
+
+        for (source, expected_code, expected_status, encoded_code) in cases {
+            let pre_stream = map_query_error_to_s3(QueryError::from(source()));
+            assert_eq!(pre_stream.code(), &expected_code);
+            assert_eq!(pre_stream.status_code(), Some(expected_status));
+            let expected_code_text = expected_code.as_str().to_string();
+            let (status, body) = http_xml_error(pre_stream).await;
+            assert_eq!(status, expected_status);
+            assert!(body.contains(&format!("<Code>{expected_code_text}</Code>")));
+            assert!(body.contains("<Message>"));
+
+            let output = Box::pin(RecordBatchStreamAdapter::new(
+                Arc::new(Schema::empty()),
+                futures::stream::once(async move { Err(source()) }),
+            ));
+            let (producer, rx, lease_released) = spawn_test_producer(output, 2);
+            producer.await.expect("producer should emit the terminal Select error");
+
+            let mut byte_stream = SelectObjectContentEventStream::new(ReceiverStream::new(rx)).into_byte_stream();
+            let mut encoded = Vec::new();
+            while let Some(chunk) = byte_stream.next().await {
+                encoded.extend_from_slice(&chunk.expect("event-stream message should serialize"));
+            }
+            let messages = event_stream_headers(&encoded);
+            let terminal_headers = messages.last().expect("event stream should contain a terminal error");
+            let encoded_code = std::str::from_utf8(encoded_code).expect("test error code should be UTF-8");
+            assert!(
+                terminal_headers
+                    .iter()
+                    .any(|(name, value)| name == ":message-type" && value == "error")
+            );
+            assert!(
+                terminal_headers
+                    .iter()
+                    .any(|(name, value)| name == ":error-code" && value == encoded_code)
+            );
+            assert!(
+                terminal_headers
+                    .iter()
+                    .any(|(name, value)| name == ":error-message" && !value.is_empty() && !value.contains("private"))
+            );
+            assert!(
+                !messages
+                    .iter()
+                    .flatten()
+                    .any(|(name, value)| { name == ":event-type" && matches!(value.as_str(), "Stats" | "End") })
+            );
+            assert!(lease_released.await.is_ok(), "error frame should release the snapshot lease");
+        }
+    }
+
+    #[tokio::test]
+    async fn sql_and_compression_errors_serialize_as_http_xml() {
+        let sql_error = map_query_error_to_s3(QueryError::Parser {
+            source: ParserError::ParserError("unexpected token".to_string()),
+        });
+        let (sql_status, sql_body) = http_xml_error(sql_error).await;
+        assert_eq!(sql_status, StatusCode::BAD_REQUEST);
+        assert!(sql_body.contains("<Code>ParseSelectFailure</Code>"));
+        assert!(sql_body.contains("<Message>"));
+
+        let mut input = base_input();
+        input.request.input_serialization.compression_type = Some(CompressionType::from_static("SNAPPY"));
+        let compression_error =
+            validate_select_request(&HeaderMap::new(), &mut input).expect_err("unknown compression must fail before streaming");
+        let (compression_status, compression_body) = http_xml_error(compression_error).await;
+        assert_eq!(compression_status, StatusCode::BAD_REQUEST);
+        assert!(compression_body.contains("<Code>InvalidCompressionFormat</Code>"));
+        assert!(compression_body.contains("<Message>"));
+    }
+
+    #[tokio::test(start_paused = true)]
+    async fn stream_error_after_records_omits_stats_and_end() {
+        let schema = Arc::new(Schema::new(vec![Field::new("value", DataType::Utf8, false)]));
+        let batch = RecordBatch::try_new(schema.clone(), vec![Arc::new(StringArray::from(vec!["row"]))])
+            .expect("test record batch should be valid");
+        let output = Box::pin(RecordBatchStreamAdapter::new(
+            schema,
+            futures::stream::iter([
+                Ok(batch),
+                Err(DataFusionError::ArrowError(
+                    Box::new(ArrowError::CsvError("private CSV parser state".to_string())),
+                    None,
+                )),
+            ]),
+        ));
+        let (producer, rx, lease_released) = spawn_test_producer(output, 3);
+
+        producer
+            .await
+            .expect("producer should emit records followed by the terminal error");
+
+        let mut byte_stream = SelectObjectContentEventStream::new(ReceiverStream::new(rx)).into_byte_stream();
+        let mut encoded = Vec::new();
+        while let Some(chunk) = byte_stream.next().await {
+            encoded.extend_from_slice(&chunk.expect("event-stream message should serialize"));
+        }
+        let messages = event_stream_headers(&encoded);
+        assert_eq!(
+            messages
+                .iter()
+                .filter_map(|headers| {
+                    headers
+                        .iter()
+                        .find_map(|(name, value)| (name == ":event-type").then_some(value.as_str()))
+                })
+                .collect::<Vec<_>>(),
+            ["Cont", "Records"]
+        );
+        let terminal_headers = messages.last().expect("stream should contain a terminal error");
+        assert!(
+            terminal_headers
+                .iter()
+                .any(|(name, value)| name == ":message-type" && value == "error")
+        );
+        assert!(
+            terminal_headers
+                .iter()
+                .any(|(name, value)| name == ":error-code" && value == "CSVParsingError")
+        );
+        assert!(
+            !messages
+                .iter()
+                .flatten()
+                .any(|(name, value)| { name == ":event-type" && matches!(value.as_str(), "Stats" | "End") })
+        );
+        assert!(lease_released.await.is_ok(), "error should release the snapshot lease");
+    }
+
     #[tokio::test(start_paused = true)]
     async fn encoder_error_uses_reserved_terminal_slot() {
         let values = ListArray::from_iter_primitive::<Int32Type, _, _>([Some([Some(1)])]);
@@ -1497,6 +1764,8 @@ mod tests {
             .expect("encoder failure should send one terminal error")
             .expect_err("terminal event should be an error");
         assert_eq!(encoder_error.code(), &S3ErrorCode::InternalError);
+        assert_eq!(encoder_error.message(), Some("An internal error occurred."));
+        assert!(encoder_error.source().is_none());
         assert!(rx.recv().await.is_none());
         assert!(lease_released.await.is_ok(), "encoder error should release the snapshot lease");
     }
@@ -1628,8 +1897,7 @@ mod tests {
         };
         assert_eq!(error.code(), &S3ErrorCode::InternalError);
         assert_eq!(snapshot_fence.0.load(std::sync::atomic::Ordering::Relaxed), 2);
-        assert!(matches!(rx.recv().await, Some(Ok(SelectObjectContentEvent::Stats(_)))));
-        assert!(rx.try_recv().is_err(), "snapshot loss after Stats must not enqueue End");
+        assert!(rx.try_recv().is_err(), "snapshot loss must not enqueue Stats or End");
     }
 
     #[test]
@@ -1658,6 +1926,27 @@ mod tests {
         );
     }
 
+    #[test]
+    fn validate_rejects_unknown_csv_header_mode_before_streaming() {
+        let mut input = base_input();
+        input
+            .request
+            .input_serialization
+            .csv
+            .as_mut()
+            .expect("base input should use CSV")
+            .file_header_info = Some(FileHeaderInfo::from_static("INVALID"));
+
+        let error = validate_select_request(&HeaderMap::new(), &mut input).expect_err("unknown header mode must fail");
+
+        assert_eq!(error.code(), &S3ErrorCode::InvalidFileHeaderInfo);
+        assert_eq!(error.status_code(), Some(StatusCode::BAD_REQUEST));
+        assert_eq!(
+            error.message(),
+            Some("The FileHeaderInfo value is not valid. Only NONE, USE, and IGNORE are supported.")
+        );
+    }
+
     #[test]
     fn validate_accepts_two_byte_csv_input_record_delimiter() {
         let mut input = base_input();
@@ -1980,26 +2269,8 @@ mod tests {
     }
 
     #[test]
-    fn map_store_error_not_found_to_no_such_key() {
-        let err = map_query_error_to_s3(QueryError::StoreError {
-            e: "ObjectStore NotFound: bucket/object.csv".to_string(),
-        });
-        assert_eq!(err.code(), &S3ErrorCode::NoSuchKey);
-    }
-
-    #[test]
-    fn map_store_error_bucket_not_found_to_no_such_bucket() {
-        let err = map_query_error_to_s3(QueryError::StoreError {
-            e: "bucket not found".to_string(),
-        });
-        assert_eq!(err.code(), &S3ErrorCode::NoSuchBucket);
-    }
-
-    #[test]
-    fn map_scan_range_store_error_to_invalid_request_parameter() {
-        let err = map_query_error_to_s3(QueryError::StoreError {
-            e: "ScanRange: Start after EOF".to_string(),
-        });
+    fn map_typed_scan_range_error_to_invalid_request_parameter() {
+        let err = map_query_error_to_s3(SelectError::InvalidScanRange.into());
         assert_eq!(err.code(), &S3ErrorCode::InvalidRequestParameter);
         assert_eq!(err.message(), Some(INVALID_SCAN_RANGE_MESSAGE));
     }