Query folding

Hi ahmedshalabyy12 

How to verify your query is folded (Databricks + Value.NativeQuery):

1. Value.NativeQuery already sends SQL to Databricks. Folding only matters for steps after that step.

2. In Power Query, right-click the last step >> View Native Query.

   • Clickable = still folded to SQL.

   • Greyed out = folding broke earlier.

3. Do a quick litmus test: add Keep Top Rows >> 5 (or filter a date). Recheck View Native Query.

   • If you see LIMIT 5 (or your WHERE clause) in the SQL, it’s folded.

4. Cross-check in Databricks >> SQL >> Query History while preview/refresh runs.

   • Your server log should show the final SQL with your filters. If it shows SELECT * and filters aren’t there, they were applied locally.

5. Remember: many steps break folding (e.g., Table.Buffer, custom M, merges with non-foldable sources). Put them after you’ve narrowed data.