Exam DP-700 topic 1 question 5 discussion

Enable V-Order: This should be your first step as it directly targets performance improvements with minimal cost. Consider the following before deciding to disable V-Order: Microsoft Fabric Direct Lake mode depends on V-Order. https://learn.microsoft.com/en-us/fabric/data-warehouse/v-order#performance-considerations

500 million rows is over the F32 table limit.

F32 supports: 300 million rows per table 40 GB model size on disk 10 GB max memory Your fact table has 500 million rows, which exceeds the supported limit for F32 in Direct Lake mode. This mismatch can cause: Visual errors Slow performance Query failures or memory overflows 🧠 Summary: If you're using Direct Lake and your table exceeds the row or memory limits of your SKU, increasing capacity is necessary to ensure stability and performance. V-Order is still a great optimization, but it won’t help if you’re over the SKU limits. ✅ Final Answer: B. Increase the capacity

Bullshit question, the V-Order is turn-on by default. But the question still ask about this :(

On a table with 500 million rows covering data from multiple years, the main cost is not the JOIN operation but scanning the huge fact table for the relevant dates — so V-Order will make more sense than changing the primary key from MD5 to SHA256.

With it saying minimize costs I thought it had to be C.

B is the correct answer. V-order is enabled by default; if you disable it, you can't turn it enable again.

V-order is enabled by default.

Vorder cant be enabled

Direct Lake mode limit 300 Mill. Fallback option mode switch to Direct Query which degrade the performance. Hence Capacity had to be increased.

Min operational Cost = Enable V Order

Why Other Options Are Unsuitable: Option: A (Change MD5→SHA256) Reason for Exclusion: Increases key size (128→256 bits), worsening storage/join performance. Option:B (Increase capacity) Reason for Exclusion:Raises costs (contradicts "minimize operational costs"). Option:D (Modify surrogate keys) Reason for Exclusion: Requires rebuilding the entire data model (high effort/cost). Option:E (Create views) Reason for Exclusion: Adds abstraction without optimizing underlying data scans.

The best option to address performance degradation while minimizing operational costs is C. Enable V-Order. Here’s why: V-Order is a storage format optimization for Delta Lake tables (used by Direct Lake mode in Power BI). It improves data skipping, which enables faster query performance by reducing the amount of data scanned. Especially with large fact tables like yours (500 million rows), enabling V-Order can have a significant impact on performance without increasing costs. It’s a low-cost, high-impact optimization since it doesn’t require more compute resources (unlike increasing capacity). Why not Improve Capacity? Effective, but it increases costs. Only do this if V-Order and other optimizations don’t solve the problem.

V-Order is a write-time optimization for Parquet files in Microsoft Fabric that significantly enhances read performance within Fabric compute engines like Power BI, SQL, and Spark. It achieves this by applying special sorting, row group distribution, dictionary encoding, and compression to the Parquet files. This optimization is crucial for Fabric's Direct Lake mode, which relies on V-Order for efficient data access

Increase the capacity is correct for me.

V-Order is a performance optimization feature for Delta tables in Fabric. It reorders data for faster analytical queries by optimizing columnar layout and file structure. Improves read performance in Direct Lake mode dramatically without extra cost. No need to reload or refactor the data, so minimal operational impact.

300 million rows is not a hard limit, but rather a performance recommendation for optimal operation under Direct Lake with F32 capacity. Your table has 500 million rows, which exceeds this recommended limit by 66% — a likely contributor to performance issues.