To reduce the number of queries sent to the database when a user interacts with a DirectQuery report using filters and slicers, what should you do?

• A. Use parameterized queries at the data source
• B. Enable auto page refresh
• C. Add apply buttons to all the basic filters
• D. Turn on query reduction in settings

Answer: (C)

When using DirectQuery, each interaction with a filter or slicer can trigger a separate database query. To cut the total number of queries, you want to batch those filter changes so they’re applied in one go. Adding apply buttons to all basic filters enforces that the user can select multiple options and then click Apply, at which point a single consolidated query runs that reflects all current selections. This reduces the number of round-trips to the database and lowers the overall query load. Other options don’t achieve this batching effect: they either don’t change how queries are issued per interaction, or they affect unrelated aspects of performance.