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// @tags: [does_not_support_stepdowns, requires_profiling]
// Confirms that profile entries for find commands contain the appropriate query hash.
(function() {
"use strict";
// For getLatestProfilerEntry
load("jstests/libs/profiler.js");
const testDB = db.getSiblingDB("query_hash");
assert.commandWorked(testDB.dropDatabase());
const coll = testDB.test;
// Utility function to list query shapes in cache. The length of the list of query shapes
// returned is used to validate the number of query hashes accumulated.
function getShapes(collection) {
const res = collection.runCommand('planCacheListQueryShapes');
return res.shapes;
}
assert.writeOK(coll.insert({a: 1, b: 1}));
assert.writeOK(coll.insert({a: 1, b: 2}));
assert.writeOK(coll.insert({a: 1, b: 2}));
assert.writeOK(coll.insert({a: 2, b: 2}));
// We need two indices since we do not currently create cache entries for queries with a single
// candidate plan.
assert.commandWorked(coll.createIndex({a: 1}));
assert.commandWorked(coll.createIndex({a: 1, b: 1}));
assert.commandWorked(testDB.setProfilingLevel(2));
// Executes query0 and gets the corresponding system.profile entry.
assert.eq(1,
coll.find({a: 1, b: 1}, {a: 1}).sort({a: -1}).comment("Query0 find command").itcount(),
'unexpected document count');
const profileObj0 =
getLatestProfilerEntry(testDB, {op: "query", "command.comment": "Query0 find command"});
assert(profileObj0.hasOwnProperty("planCacheKey"), tojson(profileObj0));
let shapes = getShapes(coll);
assert.eq(1, shapes.length, 'unexpected number of shapes in planCacheListQueryShapes result');
// Executes query1 and gets the corresponding system.profile entry.
assert.eq(0,
coll.find({a: 2, b: 1}, {a: 1}).sort({a: -1}).comment("Query1 find command").itcount(),
'unexpected document count');
const profileObj1 =
getLatestProfilerEntry(testDB, {op: "query", "command.comment": "Query1 find command"});
assert(profileObj1.hasOwnProperty("planCacheKey"), tojson(profileObj1));
// Since the query shapes are the same, we only expect there to be one query shape present in
// the plan cache commands output.
shapes = getShapes(coll);
assert.eq(1, shapes.length, 'unexpected number of shapes in planCacheListQueryShapes result');
assert.eq(
profileObj0.planCacheKey, profileObj1.planCacheKey, 'unexpected not matching query hashes');
// Test that the planCacheKey is the same in explain output for query0 and query1 as it was
// in system.profile output.
const explainQuery0 = assert.commandWorked(coll.find({a: 1, b: 1}, {a: 1})
.sort({a: -1})
.comment("Query0 find command")
.explain("queryPlanner"));
assert.eq(explainQuery0.queryPlanner.planCacheKey, profileObj0.planCacheKey, explainQuery0);
const explainQuery1 = assert.commandWorked(coll.find({a: 2, b: 1}, {a: 1})
.sort({a: -1})
.comment("Query1 find command")
.explain("queryPlanner"));
assert.eq(explainQuery1.queryPlanner.planCacheKey, profileObj0.planCacheKey, explainQuery1);
// Check that the 'planCacheKey' is the same for both query 0 and query 1.
assert.eq(explainQuery0.queryPlanner.planCacheKey, explainQuery1.queryPlanner.planCacheKey);
// Executes query2 and gets the corresponding system.profile entry.
assert.eq(0,
coll.find({a: 12000, b: 1}).comment("Query2 find command").itcount(),
'unexpected document count');
const profileObj2 =
getLatestProfilerEntry(testDB, {op: "query", "command.comment": "Query2 find command"});
assert(profileObj2.hasOwnProperty("planCacheKey"), tojson(profileObj2));
// Query0 and query1 should both have the same query hash for the given indexes. Whereas, query2
// should have a unique hash. Asserts that a total of two distinct hashes results in two query
// shapes.
shapes = getShapes(coll);
assert.eq(2, shapes.length, 'unexpected number of shapes in planCacheListQueryShapes result');
assert.neq(profileObj0.planCacheKey, profileObj2.planCacheKey, 'unexpected matching query hashes');
// The planCacheKey in explain should be different for query2 than the hash from query0 and
// query1.
const explainQuery2 = assert.commandWorked(
coll.find({a: 12000, b: 1}).comment("Query2 find command").explain("queryPlanner"));
assert(explainQuery2.queryPlanner.hasOwnProperty("planCacheKey"));
assert.neq(explainQuery2.queryPlanner.planCacheKey, profileObj0.planCacheKey, explainQuery2);
assert.eq(explainQuery2.queryPlanner.planCacheKey, profileObj2.planCacheKey, explainQuery2);
// Now drop an index. This should change the 'planCacheKey' value for queries, but not the
// 'queryHash'.
assert.commandWorked(coll.dropIndex({a: 1}));
const explainQuery2PostCatalogChange = assert.commandWorked(
coll.find({a: 12000, b: 1}).comment("Query2 find command").explain("queryPlanner"));
assert.eq(explainQuery2.queryPlanner.queryHash,
explainQuery2PostCatalogChange.queryPlanner.queryHash);
assert.neq(explainQuery2.queryPlanner.planCacheKey,
explainQuery2PostCatalogChange.queryPlanner.planCacheKey);
})();
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