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Session: Querying: How to Get Query Statistics

Query statistics can provide important information about a query like duration, total number of results, staleness information, etc. To access statistics use the statistics() method.

Syntax

query.statistics(statsCallback);

Parameters
statsCallback (stats) => void Callback passing the QueryStatistics object for query.

Example

let stats;

const employees = await session.query({ collection: "Employees" })
    .whereEquals("FirstName", "Robert")
    .statistics(s => stats = s)
    .all();

const totalResults = stats.value.totalResults;
const durationInMs = stats.value.durationInMs;
// QueryStatistics {
//   isStale: false,
//   durationInMs: 744,
//   totalResults: 1,
//   skippedResults: 0,
//   timestamp: 2018-09-24T05:34:15.260Z,
//   indexName: 'Auto/Employees/ByFirstName',
//   indexTimestamp: 2018-09-24T05:34:15.260Z,
//   lastQueryTime: 2018-09-24T05:34:15.260Z,
//   resultEtag: 8426908718162809000 }