added table comment to Table Info in SQLDatabase (#11774)

* added table comment in sql query

* handle SQL dialects without comment support

* typo in comments

llama-index-core/llama_index/core/utilities/sql_wrapper.py

@@ -150,10 +150,19 @@ class SQLDatabase:
     def get_single_table_info(self, table_name: str) -> str:
         """Get table info for a single table."""
         # same logic as table_info, but with specific table names
-        template = (
-            "Table '{table_name}' has columns: {columns}, "
-            "and foreign keys: {foreign_keys}."
-        )
+        template = "Table '{table_name}' has columns: {columns}, "
+        try:
+            # try to retrieve table comment
+            table_comment = self._inspector.get_table_comment(
+                table_name, schema=self._schema
+            )["text"]
+            if table_comment:
+                template += f"with comment: ({table_comment}) "
+        except NotImplementedError:
+            # get_table_comment raises NotImplementedError for a dialect that does not support comments.
+            pass
+
+        template += "and foreign keys: {foreign_keys}."
         columns = []
         for column in self._inspector.get_columns(table_name, schema=self._schema):
             if column.get("comment"):