Files
mongo/jstests/core/explain_find.js

44 lines
1.1 KiB
JavaScript

// Tests for explaining find through the explain command.
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"
});
printjson(explain);
assert.commandWorked(explain);
assert.eq(3, explain.executionStats.nReturned);
explain = db.runCommand({
explain: {
find: collName,
min: {a: 4},
max: {a: 6}
},
verbosity: "executionStats"
});
printjson(explain);
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);
}