fix: changes for statistics

Author: rustyconover

src/query_farm_flight_server/parameter_types.py

@@ -190,6 +190,43 @@ class ChangeColumnType(AlterBase):
     _validate_column_schema = field_validator("column_schema", mode="before")(deserialize_schema)
 
 
+class ColumnStatisticsStringResults(BaseModel):
+    max: str
+    min: str
+
+
+class ColumnStatisticsNumericValueResult(BaseModel):
+    boolean: bool | None = None
+    tinyint: int | None = None
+    smallint: int | None = None
+    integer: int | None = None
+    bigint: int | None = None
+    utinyint: int | None = None
+    usmallint: int | None = None
+    uinteger: int | None = None
+    ubigint: int | None = None
+    hugeint_high: int | None = None
+    hugeint_low: int | None = None
+    float_: float | None = None
+    double_: float | None = None
+
+
+class ColumnStatisticsNumericResults(BaseModel):
+    has_min: bool
+    has_max: bool
+
+    min: ColumnStatisticsNumericValueResult | None = None
+    max: ColumnStatisticsNumericValueResult | None = None
+
+
+class ColumnStatisticsResult(BaseModel):
+    has_null: bool
+    has_not_null: bool
+    distinct_count: int
+    string_stats: ColumnStatisticsStringResults | None = None
+    numeric_stats: ColumnStatisticsNumericResults | None = None
+
+
 class ColumnStatistics(BaseModel):
     model_config = ConfigDict(arbitrary_types_allowed=True)  # for Pydantic v2
     flight_descriptor: flight.FlightDescriptor

src/query_farm_flight_server/server.py

@@ -242,7 +242,10 @@ def __init__(
                 False,
             ),
             ActionType.COLUMN_STATISTICS: ActionHandlerSpec(
-                self.action_column_statistics, parameter_types.column_statistics, None, False
+                self.action_column_statistics,
+                parameter_types.column_statistics,
+                lambda x: x.model_dump(),
+                False,
             ),
             ActionType.CREATE_TABLE: ActionHandlerSpec(
                 self.action_create_table,
@@ -445,7 +448,7 @@ def action_column_statistics(
         *,
         context: CallContext[AccountType, TokenType],
         parameters: parameter_types.ColumnStatistics,
-    ) -> dict[str, Any]:
+    ) -> parameter_types.ColumnStatisticsResult:
         self._unimplemented_action(ActionType.COLUMN_STATISTICS)
 
     def action_drop_not_null(