mongo/jstests/core/explain_find.js

47 lines
1.4 KiB
JavaScript

// Tests for explaining find through the explain command.
(function() {
"use strict";
var collName = "jstests_explain_find";
var t = db[collName];
t.drop();
t.ensureIndex({a: 1});
for (var i = 0; i < 10; i++) {
t.insert({_id: i, a: i});
}
var explain =
db.runCommand({explain: {find: collName, filter: {a: {$lte: 2}}}, verbosity: "executionStats"});
assert.commandWorked(explain);
assert.eq(3, explain.executionStats.nReturned);
explain = db.runCommand({
explain: {find: collName, min: {a: 4}, max: {a: 6}, hint: {a: 1}},
verbosity: "executionStats",
});
assert.commandWorked(explain);
assert.eq(2, explain.executionStats.nReturned);
// Compatibility test for the $explain OP_QUERY flag. This can only run if find command is disabled.
if (!db.getMongo().useReadCommands()) {
var explain = t.find({$query: {a: 4}, $explain: true}).limit(-1).next();
assert("queryPlanner" in explain);
assert("executionStats" in explain);
assert.eq(1, explain.executionStats.nReturned);
assert("allPlansExecution" in explain.executionStats);
}
// Invalid verbosity string.
let error = assert.throws(function() {
t.explain("foobar").find().finish();
});
assert.commandFailedWithCode(error, ErrorCodes.FailedToParse);
error = assert.throws(function() {
t.find().explain("foobar");
});
assert.commandFailedWithCode(error, ErrorCodes.FailedToParse);
}());