There is a property in Power BI semantic models you can set per column called
IsAvailableInMDX. When most people discuss this property, the first question often asked is, “Are you using Excel to query the semantic model?”. If the answer is no, the usual follow up is “turn it off everywhere, you will save memory and your refresh will be faster”.For Import models, turning it off can save memory by removing a supporting structure from a column. But a DAX query may have been making good use of that structure, particularly when filtering the column. Direct Lake is different: it uses its column dictionary for these DAX optimisations, but the setting still matters for Excel field availability.
Read on to learn whether your environment might benefit from this, as well as other considerations.