Amazon Neptune
User Guide (API Version 2017-11-29)

Limitations of SPARQL Explain in Neptune

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.