In the Direct Lake mode scenario, which tool can identify loaded columns?

• A. Query the $System.DISCOVER_STORAGE_TABLE_COLUMN_SEGMENTS dynamic management view (DMV)
• B. Vertipaq Analyzer
• C. SQL Profiler
• D. Azure Monitor Logs

Answer: (A)

In Direct Lake mode, you’re dealing with data stored in the data lake and loaded on demand. To see exactly which column data is actually loaded for a given table, you inspect storage-layer metadata exposed by the system. The $System.DISCOVER_STORAGE_TABLE_COLUMN_SEGMENTS dynamic management view (DMV) provides details on the column segments for a table and indicates which ones are loaded, so you can identify the loaded columns directly from this view.

Other tools don’t serve this purpose: Vertipaq Analyzer is for the in-memory VertiPaq engine, not Direct Lake; SQL Profiler captures runtime events, and Azure Monitor Logs collects telemetry—neither shows which columns are loaded in Direct Lake mode.