# Limitations of SPARQL `explain` in Neptune
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The release of the Neptune SPARQL `explain` feature has the following limitations.

**Neptune Currently Supports Explain Only in SPARQL SELECT Queries**  
For information about the evaluation process for other query forms, such as `ASK`, `CONSTRUCT`, `DESCRIBE`, and `SPARQL UPDATE` queries, you can transform these queries into a SELECT query. Then use `explain` to inspect the corresponding SELECT query instead.

For example, to obtain `explain` information about an `ASK WHERE {...}` query, run the corresponding `SELECT WHERE {...} LIMIT 1` query with `explain`.

Similarly, for a `CONSTRUCT {...} WHERE {...}` query, drop the `CONSTRUCT {...}` part and run a `SELECT` query with `explain` on the second `WHERE {...}` clause. Evaluating the second `WHERE` clause generally reveals the main challenges of processing the `CONSTRUCT` query, because solutions flowing out of the second `WHERE` into the `CONSTRUCT` template generally only require straightforward substitution.

**Explain Operators May Change in Future Releases**  
The SPARQL `explain` operators and their parameters may change in future releases.

**Explain Output May Change in Future Releases**  
For example, column headers could change, and more columns might be added to the tables.