// @tags: [ // assumes_balancer_off, // assumes_read_concern_local, // ] (function() { 'use strict'; const t = db.index_check7; t.drop(); assert.commandWorked(t.createIndex({x: 1})); let docs = []; for (let i = 0; i < 100; i++) { docs.push({_id: i, x: i}); } assert.commandWorked(t.insert(docs)); let explainResult = t.find({x: 27}).explain(true); assert.eq(1, explainResult.executionStats.totalKeysExamined, 'explain x=27 with index {x : 1}: ' + tojson(explainResult)); assert.commandWorked(t.createIndex({x: -1})); explainResult = t.find({x: 27}).explain(true); assert.eq(1, explainResult.executionStats.totalKeysExamined, 'explain x=27 with indexes {x : 1} and {x: -1}: ' + tojson(explainResult)); explainResult = t.find({x: {$gt: 59}}).explain(true); assert.eq(40, explainResult.executionStats.totalKeysExamined, 'explain x>59 with indexes {x : 1} and {x: -1}: ' + tojson(explainResult)); })();