Query Explain report reference

Preview

This product or feature is subject to the "Pre-GA Offerings Terms" in the General Service Terms section of the Service Specific Terms. Pre-GA products and features are available "as is" and might have limited support. For more information, see the launch stage descriptions.

The following values are returned as results to operations performed with Query Explain.

Note: The Query Explain is designed for useful ad hoc analysis; its report format will evolve to maximize ease of reading and understanding, not suitability for machine processing. The returned metrics are expected to change as Datastore mode evolves (metrics may be added, removed, or updated) and are not covered by the same deprecation policy as other Firestore APIs. See the tables below for more information about stability

Plan records

Key	Type	Subject to change?	Description
indexes_used	List of Generic Structs	Yes, the contents in the Struct response are subject to change.	List of indexes selected for this query. See below.

Indexes used

The contents of indexes used are subject to change as Datastore mode evolves.

Key	Type	Description
query_scope	String	The scope at which a query is run. For example Collection, Collection Group and Includes Ancestors.
properties	String	The index fields in a format, for example (age ASC, __name__ ASC).

Execution statistics

Aggregated execution statistics for the query.

Key	Type	Field subject to change?	Description
results_returned	long	No	Total number of results returned, including entities, projections, aggregation results, keys.
execution_duration	Duration	No	Total time to execute the query in the backend.
read_operations	long	No	Total billable read operations.
debug_stats	Generic Struct	Yes, the contents in the Struct response are subject to change.	Debugging statistics from the execution of the query. See below.

Debug statistics

The following results are helpful for debugging use cases and analysis of raw, optional statistics.

The contents of debug stats are subject to change as Datastore mode evolves.

Key	Type	Description
index_entries_scanned	String	Total number of index entries inspected during the query.
documents_scanned	String	Total number of documents scanned during the query.
billing_details	Generic Struct	Billing details including metrics like: "documents_billable", "index_entries_billable", "min_query_cost".

What's next

• Learn more about running queries with explain and analyze
• Learn more about optimizing queries and indexes