How to Use SPARQL Explain to Analyze Neptune Query Execution - Amazon Neptune

How to Use SPARQL Explain to Analyze Neptune Query Execution

The SPARQL explain feature is a self-service tool in Amazon Neptune that helps you understand the execution approach taken by the Neptune engine. To invoke explain, you pass a parameter to an HTTP or HTTPS request in the form explain=mode.

The mode value can be one of static dynamic, or details:

  • In static mode, explain prints only the static structure of the query plan.

  • In dynamic mode, explain also includes dynamic aspects of the query plan. These aspects might include the number of intermediate bindings flowing through the operators, the ratio of incoming bindings to outgoing bindings, and the total time taken by operators.

  • In details mode, explain prints the information shown in dynamic mode plus additional details such as the actual SPARQL query string and the estimated range count for the pattern underlying a join operator.

Neptune supports using explain with all three SPARQL query access protocols listed in the W3C SPARQL 1.1 Protocol specification, namely:

  1. HTTP GET

  2. HTTP POST using URL-encoded parameters

  3. HTTP POST using text parameters

For information about the SPARQL query engine, see How the SPARQL Query Engine Works in Neptune.

For information about the kind of output produced by invoking SPARQL explain, see Examples of Invoking SPARQL Explain in Neptune.