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/**
* Helpers for checking correctness of generated SBE plans when expected explain() output differs.
*/
// Include helpers for analyzing explain output.
load("jstests/libs/analyze_plan.js");
load("jstests/libs/sbe_util.js");
function isIdIndexScan(db, root, expectedParentStageForIxScan) {
const parentStage = getPlanStage(root, expectedParentStageForIxScan);
if (!parentStage)
return false;
const ixscan = parentStage.inputStage;
if (!ixscan)
return false;
return ixscan.stage === "IXSCAN" && !ixscan.hasOwnProperty("filter") &&
ixscan.indexName === "_id_";
}
/**
* Given the root stage of agg explain's JSON representation of a query plan ('queryLayerOutput'),
* returns all sub-documents whose stage is 'stage'. This can be a SBE stage name like "nlj" or
* "hash_lookup".
*
* Returns an empty array if the plan does not have the requested stage. Asserts that agg explain
* structure matches expected format.
*/
function getSbePlanStages(queryLayerOutput, stage) {
assert(queryLayerOutput);
const queryInfo = getQueryInfoAtTopLevelOrFirstStage(queryLayerOutput);
// If execution stats are available, then use the execution stats tree.
if (queryInfo.hasOwnProperty("executionStats")) {
assert(queryInfo.executionStats.hasOwnProperty("executionStages"), queryInfo);
return getPlanStages(queryInfo.executionStats.executionStages, stage);
}
// Otherwise, we won't extract from the 'queryPlanner' for now.
return [];
}
/**
* Helper to make an assertion depending on the engine being used. If we're in a mixed version
* cluster, then we assert that either 'classicAssert' or 'sbeAssert' is true because the outcome
* will depend on which node we're making assertions against. If we're not in a mixed version
* scenario, then we make an assertion depending on the return value of 'checkSBEEnabled'.
*/
function engineSpecificAssertion(classicAssert, sbeAssert, theDB, msg) {
if (checkBothEnginesAreRunOnCluster(theDB)) {
assert(classicAssert || sbeAssert, msg);
} else if (checkSBEEnabled(theDB, ["featureFlagSbeFull"])) {
// This function assumes that SBE is fully enabled, and will fall back to the classic
// assert if it is not.
assert(sbeAssert, msg);
} else {
assert(classicAssert, msg);
}
}
/**
* Gets the query info object at either the top level or the first stage from a v2
* explainOutput. If a query is a find query or some prefix stage(s) of a pipeline is pushed down to
* SBE, then plan information will be in the 'queryPlanner' object. Currently, this supports find
* query or pushed-down prefix pipeline stages.
*/
function getQueryInfoAtTopLevelOrFirstStage(explainOutputV2) {
if (explainOutputV2.hasOwnProperty("queryPlanner")) {
return explainOutputV2;
}
if (explainOutputV2.hasOwnProperty("stages") && Array.isArray(explainOutputV2.stages) &&
explainOutputV2.stages.length > 0 && explainOutputV2.stages[0].hasOwnProperty("$cursor") &&
explainOutputV2.stages[0].$cursor.hasOwnProperty("queryPlanner")) {
return explainOutputV2.stages[0].$cursor;
}
if (explainOutputV2.hasOwnProperty("shards")) {
for (const shardName in explainOutputV2.shards) {
const shardExplainOutputV2 = explainOutputV2.shards[shardName];
return getQueryInfoAtTopLevelOrFirstStage(shardExplainOutputV2);
}
}
assert(false, `expected version 2 explain output but got ${JSON.stringify(explainOutputV2)}`);
return undefined;
}
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