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/**
* Test $merge and exchange with explain.
*
* @tags: [requires_sharding]
*/
load('jstests/aggregation/extras/utils.js');
(function() {
"use strict";
const st = new ShardingTest({shards: 2, rs: {nodes: 1}});
const mongosDB = st.s.getDB("test_db");
const inColl = mongosDB["inColl"];
const targetCollRange = mongosDB["targetCollRange"];
const targetCollRangeOtherField = mongosDB["targetCollRangeOtherField"];
const targetCollHash = mongosDB["targetCollHash"];
const numDocs = 1000;
function runExplainQuery(targetColl) {
return inColl.explain("allPlansExecution").aggregate([
{$group: {_id: "$a", a: {$avg: "$a"}}},
{
$merge: {
into: {
db: targetColl.getDB().getName(),
coll: targetColl.getName(),
},
whenMatched: "replace",
whenNotMatched: "insert"
}
}
]);
}
function runRealQuery(targetColl) {
return inColl.aggregate([
{$group: {_id: "$a", a: {$avg: "$a"}}},
{
$merge: {
into: {
db: targetColl.getDB().getName(),
coll: targetColl.getName(),
},
whenMatched: "replace",
whenNotMatched: "insert"
}
}
]);
}
function getExchangeSpec(explain) {
assert(explain.hasOwnProperty("splitPipeline"), tojson(explain));
assert(explain.splitPipeline.hasOwnProperty("exchange"), tojson(explain));
return explain.splitPipeline.exchange;
}
// Shard the input collection.
st.shardColl(inColl, {a: 1}, {a: 500}, {a: 500}, mongosDB.getName());
// Insert some data to the input collection.
let bulk = inColl.initializeUnorderedBulkOp();
for (let i = 0; i < numDocs; i++) {
bulk.insert({a: i}, {b: [0, 1, 2, 3, i]});
}
assert.commandWorked(bulk.execute());
// Shard the output collections.
st.shardColl(targetCollRange, {_id: 1}, {_id: 500}, {_id: 500}, mongosDB.getName());
st.shardColl(targetCollRangeOtherField, {b: 1}, {b: 500}, {b: 500}, mongosDB.getName());
st.shardColl(targetCollHash, {_id: "hashed"}, false, false, mongosDB.getName());
// Run the explain. We expect to see the range based exchange here.
let explain = runExplainQuery(targetCollRange);
// Make sure we see the exchange in the explain output.
assert.eq(explain.mergeType, "exchange", tojson(explain));
let exchangeSpec = getExchangeSpec(explain);
assert.eq(exchangeSpec.policy, "keyRange");
assert.eq(exchangeSpec.key, {_id: 1});
// Run the real query.
runRealQuery(targetCollRange);
let results = targetCollRange.aggregate([{'$count': "count"}]).next().count;
assert.eq(results, numDocs);
// Rerun the same query with the hash based exchange.
explain = runExplainQuery(targetCollHash);
// Make sure we see the exchange in the explain output.
assert.eq(explain.mergeType, "exchange", tojson(explain));
exchangeSpec = getExchangeSpec(explain);
assert.eq(exchangeSpec.policy, "keyRange");
assert.eq(exchangeSpec.key, {_id: "hashed"});
// Run the real query.
runRealQuery(targetCollHash);
results = targetCollHash.aggregate([{'$count': "count"}]).next().count;
assert.eq(results, numDocs);
// This should fail because the "on" field ('b' in this case, the shard key of the target
// collection) cannot be an array.
assertErrorCode(inColl,
[{
$merge: {
into: {
db: targetCollRangeOtherField.getDB().getName(),
coll: targetCollRangeOtherField.getName(),
},
whenMatched: "replace",
whenNotMatched: "insert"
}
}],
51132);
// Turn off the exchange and rerun the query.
assert.commandWorked(mongosDB.adminCommand({setParameter: 1, internalQueryDisableExchange: 1}));
explain = runExplainQuery(targetCollRange);
// Make sure there is no exchange.
assert.eq(explain.mergeType, "anyShard", tojson(explain));
assert(explain.hasOwnProperty("splitPipeline"), tojson(explain));
assert(!explain.splitPipeline.hasOwnProperty("exchange"), tojson(explain));
// This should fail similar to before even if we are not running the exchange.
assertErrorCode(inColl,
[{
$merge: {
into: {
db: targetCollRangeOtherField.getDB().getName(),
coll: targetCollRangeOtherField.getName(),
},
whenMatched: "replace",
whenNotMatched: "insert"
}
}],
51132);
// SERVER-38349 Make sure mongos rejects specifying exchange directly.
assert.commandFailedWithCode(mongosDB.runCommand({
aggregate: inColl.getName(),
pipeline: [],
cursor: {},
exchange: {
policy: "keyRange",
bufferSize: NumberInt(1024),
boundaries: [{_id: 0}],
consumers: NumberInt(2),
consumerIds: [NumberInt(0), NumberInt(1)]
}
}),
51028);
assert.commandFailedWithCode(mongosDB.runCommand({
aggregate: inColl.getName(),
pipeline: [{
$merge: {
into: targetCollRange.getName(),
whenMatched: "replace",
whenNotMatched: "insert"
}
}],
cursor: {},
exchange: {
policy: "keyRange",
bufferSize: NumberInt(1024),
boundaries: [{_id: 0}],
consumers: NumberInt(2),
consumerIds: [NumberInt(0), NumberInt(1)]
}
}),
51028);
st.stop();
}());
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