added a val func to check if location is provided if table does not e…

…xist

Signed-off-by: Minura Punchihewa <minurapunchihewa17@gmail.com>

kedro-datasets/kedro_datasets/databricks/_base_table_dataset.py

@@ -11,9 +11,9 @@
 import pandas as pd
 from kedro.io.core import (
     AbstractVersionedDataset,
+    DatasetError,
     Version,
-    VersionNotFoundError,
-    DatasetError
+    VersionNotFoundError
 )
 from pyspark.sql import DataFrame
 from pyspark.sql.readwriter import DataFrameWriter
@@ -84,7 +84,7 @@ def _validate_table(self):
             DatasetError: If the table name does not conform to naming constraints.
         """
         if not re.fullmatch(self._NAMING_REGEX, self.table):
-            raise DatasetError("table does not conform to naming")
+            raise DatasetError("Table does not conform to naming")
 
     def _validate_database(self):
         """Validates database name.
@@ -93,7 +93,7 @@ def _validate_database(self):
             DatasetError: If the dataset name does not conform to naming constraints.
         """
         if not re.fullmatch(self._NAMING_REGEX, self.database):
-            raise DatasetError("database does not conform to naming")
+            raise DatasetError("Database does not conform to naming")
 
     def _validate_catalog(self):
         """Validates catalog name.
@@ -103,7 +103,7 @@ def _validate_catalog(self):
         """
         if self.catalog:
             if not re.fullmatch(self._NAMING_REGEX, self.catalog):
-                raise DatasetError("catalog does not conform to naming")
+                raise DatasetError("Catalog does not conform to naming")
 
     def _validate_write_mode(self):
         """Validates the write mode.

kedro-datasets/kedro_datasets/databricks/external_table_dataset.py

@@ -8,6 +8,10 @@
 from typing import Any
 
 import pandas as pd
+import pandas as pd
+from kedro.io.core import (
+    DatasetError
+)
 
 from kedro_datasets.databricks._base_table_dataset import BaseTable, BaseTableDataset
 
@@ -19,6 +23,18 @@
 class ExternalTable(BaseTable):
     """Stores the definition of an external table."""
 
+    def _validate_existence_of_table(self) -> None:
+        """Validates that a location is provided if the table does not exist.
+        
+        Raises:
+            DatasetError: If the table does not exist and no location is provided.
+        """
+        if not self.exists() and not self.location:
+            raise DatasetError(
+                "If the external table does not exists, the `location` parameter must be provided. "
+                "This should be valid path in an external location that has already been created."
+            )
+
 
 class ExternalTableDataset(BaseTableDataset):
     """``ExternalTableDataset`` loads and saves data into external tables in Databricks.