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explain
Returns planning information for find, aggregate, count, or distinct. The default gateway does not explain write commands.
db.flights.find({ status: "Delayed" }).explain("executionStats")| Parameter | Description |
|---|---|
explain | (Required) A document specifying the nested read command, with the same options as its command page. |
verbosity | (Optional) A string selecting queryPlanner (default), executionStats, or allPlansExecution. DocumentDB also recognizes allShardsQueryPlan and allShardsExecution for distributed diagnostics. |
allPlansExecution provides detailed execution plans, including cursor-based planning details, alongside execution statistics. Use it to investigate how a cursor query is planned.
Execution-statistics modes execute the underlying read to collect statistics. An unrecognized verbosity string follows the implementation's default mode rather than selecting a new diagnostic mode. aggregate also accepts explain: true directly.
See wire protocol and common fields. Source: gateway explain/mod.rs, process_explain and Verbosity.