Deprecating sql_database access for creating UC functions for agent tools (#29745)

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---------

Co-authored-by: ccurme <chester.curme@gmail.com>

libs/community/langchain_community/utilities/sql_database.py

@@ -139,6 +139,14 @@ class SQLDatabase:
         return cls(create_engine(database_uri, **_engine_args), **kwargs)
 
     @classmethod
+    @deprecated(
+        "0.3.18",
+        message="For performing structured retrieval using Databricks SQL, "
+        "see the latest best practices and recommended APIs at "
+        "https://docs.unitycatalog.io/ai/integrations/langchain/ "  # noqa: E501
+        "instead",
+        removal="1.0",
+    )
     def from_databricks(
         cls,
         catalog: str,