Status SubplanRunner::planSubqueries() {
MatchExpression* theOr = _query->root();
for (size_t i = 0; i < _plannerParams.indices.size(); ++i) {
const IndexEntry& ie = _plannerParams.indices[i];
_indexMap[ie.keyPattern] = i;
QLOG() << "Subplanner: index " << i << " is " << ie.toString() << endl;
}
const WhereCallbackReal whereCallback(_collection->ns().db());
for (size_t i = 0; i < theOr->numChildren(); ++i) {
// Turn the i-th child into its own query.
MatchExpression* orChild = theOr->getChild(i);
CanonicalQuery* orChildCQ;
Status childCQStatus = CanonicalQuery::canonicalize(*_query,
orChild,
&orChildCQ,
whereCallback);
if (!childCQStatus.isOK()) {
mongoutils::str::stream ss;
ss << "Subplanner: Can't canonicalize subchild " << orChild->toString()
<< " " << childCQStatus.reason();
return Status(ErrorCodes::BadValue, ss);
}
// Make sure it gets cleaned up.
auto_ptr<CanonicalQuery> safeOrChildCQ(orChildCQ);
// Plan the i-th child.
vector<QuerySolution*> solutions;
// We don't set NO_TABLE_SCAN because peeking at the cache data will keep us from
// considering any plan that's a collscan.
QLOG() << "Subplanner: planning child " << i << " of " << theOr->numChildren();
Status status = QueryPlanner::plan(*safeOrChildCQ, _plannerParams, &solutions);
if (!status.isOK()) {
mongoutils::str::stream ss;
ss << "Subplanner: Can't plan for subchild " << orChildCQ->toString()
<< " " << status.reason();
return Status(ErrorCodes::BadValue, ss);
}
QLOG() << "Subplanner: got " << solutions.size() << " solutions";
if (0 == solutions.size()) {
// If one child doesn't have an indexed solution, bail out.
mongoutils::str::stream ss;
ss << "Subplanner: No solutions for subchild " << orChildCQ->toString();
return Status(ErrorCodes::BadValue, ss);
}
// Hang onto the canonicalized subqueries and the corresponding query solutions
// so that they can be used in subplan running later on.
_cqs.push(safeOrChildCQ.release());
_solutions.push(solutions);
}
return Status::OK();
}
// static
MatchExpression* CanonicalQuery::normalizeTree(MatchExpression* root) {
// root->isLogical() is true now. We care about AND, OR, and NOT. NOR currently scares us.
if (MatchExpression::AND == root->matchType() || MatchExpression::OR == root->matchType()) {
// We could have AND of AND of AND. Make sure we clean up our children before merging
// them.
// UNITTEST 11738048
for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
(*root->getChildVector())[i] = normalizeTree(root->getChild(i));
}
// If any of our children are of the same logical operator that we are, we remove the
// child's children and append them to ourselves after we examine all children.
std::vector<MatchExpression*> absorbedChildren;
for (size_t i = 0; i < root->numChildren();) {
MatchExpression* child = root->getChild(i);
if (child->matchType() == root->matchType()) {
// AND of an AND or OR of an OR. Absorb child's children into ourself.
for (size_t j = 0; j < child->numChildren(); ++j) {
absorbedChildren.push_back(child->getChild(j));
}
// TODO(opt): this is possibly n^2-ish
root->getChildVector()->erase(root->getChildVector()->begin() + i);
child->getChildVector()->clear();
// Note that this only works because we cleared the child's children
delete child;
// Don't increment 'i' as the current child 'i' used to be child 'i+1'
} else {
++i;
}
}
root->getChildVector()->insert(
root->getChildVector()->end(), absorbedChildren.begin(), absorbedChildren.end());
// AND of 1 thing is the thing, OR of 1 thing is the thing.
if (1 == root->numChildren()) {
MatchExpression* ret = root->getChild(0);
root->getChildVector()->clear();
delete root;
return ret;
}
} else if (MatchExpression::NOT == root->matchType()) {
// Normalize the rest of the tree hanging off this NOT node.
NotMatchExpression* nme = static_cast<NotMatchExpression*>(root);
MatchExpression* child = nme->releaseChild();
// normalizeTree(...) takes ownership of 'child', and then
// transfers ownership of its return value to 'nme'.
nme->resetChild(normalizeTree(child));
} else if (MatchExpression::ELEM_MATCH_VALUE == root->matchType()) {
// Just normalize our children.
for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
(*root->getChildVector())[i] = normalizeTree(root->getChild(i));
}
}
return root;
}
// static
MatchExpression* CanonicalQuery::normalizeTree(MatchExpression* root) {
// root->isLogical() is true now. We care about AND and OR. Negations currently scare us.
if (MatchExpression::AND == root->matchType() || MatchExpression::OR == root->matchType()) {
// We could have AND of AND of AND. Make sure we clean up our children before merging
// them.
// UNITTEST 11738048
for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
(*root->getChildVector())[i] = normalizeTree(root->getChild(i));
}
// If any of our children are of the same logical operator that we are, we remove the
// child's children and append them to ourselves after we examine all children.
vector<MatchExpression*> absorbedChildren;
for (size_t i = 0; i < root->numChildren();) {
MatchExpression* child = root->getChild(i);
if (child->matchType() == root->matchType()) {
// AND of an AND or OR of an OR. Absorb child's children into ourself.
for (size_t j = 0; j < child->numChildren(); ++j) {
absorbedChildren.push_back(child->getChild(j));
}
// TODO(opt): this is possibly n^2-ish
root->getChildVector()->erase(root->getChildVector()->begin() + i);
child->getChildVector()->clear();
// Note that this only works because we cleared the child's children
delete child;
// Don't increment 'i' as the current child 'i' used to be child 'i+1'
}
else {
++i;
}
}
root->getChildVector()->insert(root->getChildVector()->end(),
absorbedChildren.begin(),
absorbedChildren.end());
// AND of 1 thing is the thing, OR of 1 thing is the thing.
if (1 == root->numChildren()) {
MatchExpression* ret = root->getChild(0);
root->getChildVector()->clear();
delete root;
return ret;
}
}
return root;
}
bool isIndependentOf(const MatchExpression& expr, const std::set<std::string>& pathSet) {
if (expr.isLogical()) {
// Any logical expression is independent of 'pathSet' if all its children are independent of
// 'pathSet'.
for (size_t i = 0; i < expr.numChildren(); i++) {
if (!isIndependentOf(*expr.getChild(i), pathSet)) {
return false;
}
}
return true;
}
// At this point, we know 'expr' is a leaf. If it is an elemMatch, we do not attempt to
// determine if it is independent or not, and instead just return false.
return !isElemMatch(expr) && isLeafIndependentOf(expr.path(), pathSet);
}
static Status _extractFullEqualityMatches(const MatchExpression& root,
const FieldRefSet* fullPathsToExtract,
EqualityMatches* equalities) {
if (root.matchType() == MatchExpression::EQ) {
// Extract equality matches
const EqualityMatchExpression& eqChild =
static_cast<const EqualityMatchExpression&>(root);
FieldRef path(eqChild.path());
if (fullPathsToExtract) {
FieldRefSet conflictPaths;
fullPathsToExtract->findConflicts(&path, &conflictPaths);
// Ignore if this path is unrelated to the full paths
if (conflictPaths.empty())
return Status::OK();
// Make sure we're a prefix of all the conflict paths
Status status = checkPathIsPrefixOf(path, conflictPaths);
if (!status.isOK())
return status;
}
Status status = checkEqualityConflicts(*equalities, path);
if (!status.isOK())
return status;
equalities->insert(make_pair(eqChild.path(), &eqChild));
}
else if (root.matchType() == MatchExpression::AND) {
// Further explore $and matches
for (size_t i = 0; i < root.numChildren(); ++i) {
MatchExpression* child = root.getChild(i);
Status status = _extractFullEqualityMatches(*child, fullPathsToExtract, equalities);
if (!status.isOK())
return status;
}
}
return Status::OK();
}
Status SubplanStage::planSubqueries() {
// Adds the amount of time taken by planSubqueries() to executionTimeMillis. There's lots of
// work that happens here, so this is needed for the time accounting to make sense.
ScopedTimer timer(&_commonStats.executionTimeMillis);
MatchExpression* orExpr = _query->root();
for (size_t i = 0; i < _plannerParams.indices.size(); ++i) {
const IndexEntry& ie = _plannerParams.indices[i];
_indexMap[ie.keyPattern] = i;
QLOG() << "Subplanner: index " << i << " is " << ie.toString() << endl;
}
const WhereCallbackReal whereCallback(_txn, _collection->ns().db());
for (size_t i = 0; i < orExpr->numChildren(); ++i) {
// We need a place to shove the results from planning this branch.
_branchResults.push_back(new BranchPlanningResult());
BranchPlanningResult* branchResult = _branchResults.back();
MatchExpression* orChild = orExpr->getChild(i);
// Turn the i-th child into its own query.
{
CanonicalQuery* orChildCQ;
Status childCQStatus = CanonicalQuery::canonicalize(*_query,
orChild,
&orChildCQ,
whereCallback);
if (!childCQStatus.isOK()) {
mongoutils::str::stream ss;
ss << "Can't canonicalize subchild " << orChild->toString()
<< " " << childCQStatus.reason();
return Status(ErrorCodes::BadValue, ss);
}
branchResult->canonicalQuery.reset(orChildCQ);
}
// Plan the i-th child. We might be able to find a plan for the i-th child in the plan
// cache. If there's no cached plan, then we generate and rank plans using the MPS.
CachedSolution* rawCS;
if (PlanCache::shouldCacheQuery(*branchResult->canonicalQuery.get()) &&
_collection->infoCache()->getPlanCache()->get(*branchResult->canonicalQuery.get(),
&rawCS).isOK()) {
// We have a CachedSolution. Store it for later.
QLOG() << "Subplanner: cached plan found for child " << i << " of "
<< orExpr->numChildren();
branchResult->cachedSolution.reset(rawCS);
}
else {
// No CachedSolution found. We'll have to plan from scratch.
QLOG() << "Subplanner: planning child " << i << " of " << orExpr->numChildren();
// We don't set NO_TABLE_SCAN because peeking at the cache data will keep us from
// considering any plan that's a collscan.
Status status = QueryPlanner::plan(*branchResult->canonicalQuery.get(),
_plannerParams,
&branchResult->solutions.mutableVector());
if (!status.isOK()) {
mongoutils::str::stream ss;
ss << "Can't plan for subchild "
<< branchResult->canonicalQuery->toString()
<< " " << status.reason();
return Status(ErrorCodes::BadValue, ss);
}
QLOG() << "Subplanner: got " << branchResult->solutions.size() << " solutions";
if (0 == branchResult->solutions.size()) {
// If one child doesn't have an indexed solution, bail out.
mongoutils::str::stream ss;
ss << "No solutions for subchild " << branchResult->canonicalQuery->toString();
return Status(ErrorCodes::BadValue, ss);
}
}
}
return Status::OK();
}
// static
MatchExpression* CanonicalQuery::normalizeTree(MatchExpression* root) {
if (MatchExpression::AND == root->matchType() || MatchExpression::OR == root->matchType()) {
// We could have AND of AND of AND. Make sure we clean up our children before merging them.
for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
(*root->getChildVector())[i] = normalizeTree(root->getChild(i));
}
// If any of our children are of the same logical operator that we are, we remove the
// child's children and append them to ourselves after we examine all children.
std::vector<MatchExpression*> absorbedChildren;
for (size_t i = 0; i < root->numChildren();) {
MatchExpression* child = root->getChild(i);
if (child->matchType() == root->matchType()) {
// AND of an AND or OR of an OR. Absorb child's children into ourself.
for (size_t j = 0; j < child->numChildren(); ++j) {
absorbedChildren.push_back(child->getChild(j));
}
// TODO(opt): this is possibly n^2-ish
root->getChildVector()->erase(root->getChildVector()->begin() + i);
child->getChildVector()->clear();
// Note that this only works because we cleared the child's children
delete child;
// Don't increment 'i' as the current child 'i' used to be child 'i+1'
} else {
++i;
}
}
root->getChildVector()->insert(
root->getChildVector()->end(), absorbedChildren.begin(), absorbedChildren.end());
// AND of 1 thing is the thing, OR of 1 thing is the thing.
if (1 == root->numChildren()) {
MatchExpression* ret = root->getChild(0);
root->getChildVector()->clear();
delete root;
return ret;
}
} else if (MatchExpression::NOR == root->matchType()) {
// First clean up children.
for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
(*root->getChildVector())[i] = normalizeTree(root->getChild(i));
}
// NOR of one thing is NOT of the thing.
if (1 == root->numChildren()) {
// Detach the child and assume ownership.
std::unique_ptr<MatchExpression> child(root->getChild(0));
root->getChildVector()->clear();
// Delete the root when this goes out of scope.
std::unique_ptr<NorMatchExpression> ownedRoot(static_cast<NorMatchExpression*>(root));
// Make a NOT to be the new root and transfer ownership of the child to it.
auto newRoot = stdx::make_unique<NotMatchExpression>();
newRoot->init(child.release()).transitional_ignore();
return newRoot.release();
}
} else if (MatchExpression::NOT == root->matchType()) {
// Normalize the rest of the tree hanging off this NOT node.
NotMatchExpression* nme = static_cast<NotMatchExpression*>(root);
MatchExpression* child = nme->releaseChild();
// normalizeTree(...) takes ownership of 'child', and then
// transfers ownership of its return value to 'nme'.
nme->resetChild(normalizeTree(child));
} else if (MatchExpression::ELEM_MATCH_OBJECT == root->matchType()) {
// Normalize the rest of the tree hanging off this ELEM_MATCH_OBJECT node.
ElemMatchObjectMatchExpression* emome = static_cast<ElemMatchObjectMatchExpression*>(root);
auto child = emome->releaseChild();
// normalizeTree(...) takes ownership of 'child', and then
// transfers ownership of its return value to 'emome'.
emome->resetChild(std::unique_ptr<MatchExpression>(normalizeTree(child.release())));
} else if (MatchExpression::ELEM_MATCH_VALUE == root->matchType()) {
// Just normalize our children.
for (size_t i = 0; i < root->getChildVector()->size(); ++i) {
(*root->getChildVector())[i] = normalizeTree(root->getChild(i));
}
} else if (MatchExpression::MATCH_IN == root->matchType()) {
std::unique_ptr<InMatchExpression> in(static_cast<InMatchExpression*>(root));
// IN of 1 regex is the regex.
if (in->getRegexes().size() == 1 && in->getEqualities().empty()) {
RegexMatchExpression* childRe = in->getRegexes().begin()->get();
invariant(!childRe->getTag());
// Create a new RegexMatchExpression, because 'childRe' does not have a path.
auto re = stdx::make_unique<RegexMatchExpression>();
re->init(in->path(), childRe->getString(), childRe->getFlags()).transitional_ignore();
if (in->getTag()) {
re->setTag(in->getTag()->clone());
}
return normalizeTree(re.release());
}
// IN of 1 equality is the equality.
if (in->getEqualities().size() == 1 && in->getRegexes().empty()) {
auto eq = stdx::make_unique<EqualityMatchExpression>();
eq->init(in->path(), *(in->getEqualities().begin())).transitional_ignore();
eq->setCollator(in->getCollator());
if (in->getTag()) {
eq->setTag(in->getTag()->clone());
}
return eq.release();
}
return in.release();
}
return root;
}
// static
Status QueryPlanner::plan(const CanonicalQuery& query,
const QueryPlannerParams& params,
std::vector<QuerySolution*>* out) {
LOG(5) << "Beginning planning..." << endl
<< "=============================" << endl
<< "Options = " << optionString(params.options) << endl
<< "Canonical query:" << endl
<< query.toString() << "=============================" << endl;
for (size_t i = 0; i < params.indices.size(); ++i) {
LOG(5) << "Index " << i << " is " << params.indices[i].toString() << endl;
}
bool canTableScan = !(params.options & QueryPlannerParams::NO_TABLE_SCAN);
// If the query requests a tailable cursor, the only solution is a collscan + filter with
// tailable set on the collscan. TODO: This is a policy departure. Previously I think you
// could ask for a tailable cursor and it just tried to give you one. Now, we fail if we
// can't provide one. Is this what we want?
if (query.getParsed().isTailable()) {
if (!QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR) && canTableScan) {
QuerySolution* soln = buildCollscanSoln(query, true, params);
if (NULL != soln) {
out->push_back(soln);
}
}
return Status::OK();
}
// The hint or sort can be $natural: 1. If this happens, output a collscan. If both
// a $natural hint and a $natural sort are specified, then the direction of the collscan
// is determined by the sign of the sort (not the sign of the hint).
if (!query.getParsed().getHint().isEmpty() || !query.getParsed().getSort().isEmpty()) {
BSONObj hintObj = query.getParsed().getHint();
BSONObj sortObj = query.getParsed().getSort();
BSONElement naturalHint = hintObj.getFieldDotted("$natural");
BSONElement naturalSort = sortObj.getFieldDotted("$natural");
// A hint overrides a $natural sort. This means that we don't force a table
// scan if there is a $natural sort with a non-$natural hint.
if (!naturalHint.eoo() || (!naturalSort.eoo() && hintObj.isEmpty())) {
LOG(5) << "Forcing a table scan due to hinted $natural\n";
// min/max are incompatible with $natural.
if (canTableScan && query.getParsed().getMin().isEmpty() &&
query.getParsed().getMax().isEmpty()) {
QuerySolution* soln = buildCollscanSoln(query, false, params);
if (NULL != soln) {
out->push_back(soln);
}
}
return Status::OK();
}
}
// Figure out what fields we care about.
unordered_set<string> fields;
QueryPlannerIXSelect::getFields(query.root(), "", &fields);
for (unordered_set<string>::const_iterator it = fields.begin(); it != fields.end(); ++it) {
LOG(5) << "Predicate over field '" << *it << "'" << endl;
}
// Filter our indices so we only look at indices that are over our predicates.
vector<IndexEntry> relevantIndices;
// Hints require us to only consider the hinted index.
// If index filters in the query settings were used to override
// the allowed indices for planning, we should not use the hinted index
// requested in the query.
BSONObj hintIndex;
if (!params.indexFiltersApplied) {
hintIndex = query.getParsed().getHint();
}
// Snapshot is a form of a hint. If snapshot is set, try to use _id index to make a real
// plan. If that fails, just scan the _id index.
if (query.getParsed().isSnapshot()) {
// Find the ID index in indexKeyPatterns. It's our hint.
for (size_t i = 0; i < params.indices.size(); ++i) {
if (isIdIndex(params.indices[i].keyPattern)) {
hintIndex = params.indices[i].keyPattern;
break;
}
}
}
size_t hintIndexNumber = numeric_limits<size_t>::max();
if (hintIndex.isEmpty()) {
QueryPlannerIXSelect::findRelevantIndices(fields, params.indices, &relevantIndices);
} else {
// Sigh. If the hint is specified it might be using the index name.
BSONElement firstHintElt = hintIndex.firstElement();
if (str::equals("$hint", firstHintElt.fieldName()) && String == firstHintElt.type()) {
string hintName = firstHintElt.String();
for (size_t i = 0; i < params.indices.size(); ++i) {
if (params.indices[i].name == hintName) {
LOG(5) << "Hint by name specified, restricting indices to "
<< params.indices[i].keyPattern.toString() << endl;
relevantIndices.clear();
relevantIndices.push_back(params.indices[i]);
hintIndexNumber = i;
hintIndex = params.indices[i].keyPattern;
break;
}
}
} else {
for (size_t i = 0; i < params.indices.size(); ++i) {
if (0 == params.indices[i].keyPattern.woCompare(hintIndex)) {
relevantIndices.clear();
relevantIndices.push_back(params.indices[i]);
LOG(5) << "Hint specified, restricting indices to " << hintIndex.toString()
<< endl;
hintIndexNumber = i;
break;
}
}
}
if (hintIndexNumber == numeric_limits<size_t>::max()) {
return Status(ErrorCodes::BadValue, "bad hint");
}
}
// Deal with the .min() and .max() query options. If either exist we can only use an index
// that matches the object inside.
if (!query.getParsed().getMin().isEmpty() || !query.getParsed().getMax().isEmpty()) {
BSONObj minObj = query.getParsed().getMin();
BSONObj maxObj = query.getParsed().getMax();
// The unfinished siblings of these objects may not be proper index keys because they
// may be empty objects or have field names. When an index is picked to use for the
// min/max query, these "finished" objects will always be valid index keys for the
// index's key pattern.
BSONObj finishedMinObj;
BSONObj finishedMaxObj;
// This is the index into params.indices[...] that we use.
size_t idxNo = numeric_limits<size_t>::max();
// If there's an index hinted we need to be able to use it.
if (!hintIndex.isEmpty()) {
if (!minObj.isEmpty() && !indexCompatibleMaxMin(minObj, hintIndex)) {
LOG(5) << "Minobj doesn't work with hint";
return Status(ErrorCodes::BadValue, "hint provided does not work with min query");
}
if (!maxObj.isEmpty() && !indexCompatibleMaxMin(maxObj, hintIndex)) {
LOG(5) << "Maxobj doesn't work with hint";
return Status(ErrorCodes::BadValue, "hint provided does not work with max query");
}
const BSONObj& kp = params.indices[hintIndexNumber].keyPattern;
finishedMinObj = finishMinObj(kp, minObj, maxObj);
finishedMaxObj = finishMaxObj(kp, minObj, maxObj);
// The min must be less than the max for the hinted index ordering.
if (0 <= finishedMinObj.woCompare(finishedMaxObj, kp, false)) {
LOG(5) << "Minobj/Maxobj don't work with hint";
return Status(ErrorCodes::BadValue,
"hint provided does not work with min/max query");
}
idxNo = hintIndexNumber;
} else {
// No hinted index, look for one that is compatible (has same field names and
// ordering thereof).
for (size_t i = 0; i < params.indices.size(); ++i) {
const BSONObj& kp = params.indices[i].keyPattern;
BSONObj toUse = minObj.isEmpty() ? maxObj : minObj;
if (indexCompatibleMaxMin(toUse, kp)) {
// In order to be fully compatible, the min has to be less than the max
// according to the index key pattern ordering. The first step in verifying
// this is "finish" the min and max by replacing empty objects and stripping
// field names.
finishedMinObj = finishMinObj(kp, minObj, maxObj);
finishedMaxObj = finishMaxObj(kp, minObj, maxObj);
// Now we have the final min and max. This index is only relevant for
// the min/max query if min < max.
if (0 >= finishedMinObj.woCompare(finishedMaxObj, kp, false)) {
// Found a relevant index.
idxNo = i;
break;
}
// This index is not relevant; move on to the next.
}
}
}
if (idxNo == numeric_limits<size_t>::max()) {
LOG(5) << "Can't find relevant index to use for max/min query";
// Can't find an index to use, bail out.
return Status(ErrorCodes::BadValue, "unable to find relevant index for max/min query");
}
LOG(5) << "Max/min query using index " << params.indices[idxNo].toString() << endl;
// Make our scan and output.
QuerySolutionNode* solnRoot = QueryPlannerAccess::makeIndexScan(
params.indices[idxNo], query, params, finishedMinObj, finishedMaxObj);
QuerySolution* soln = QueryPlannerAnalysis::analyzeDataAccess(query, params, solnRoot);
if (NULL != soln) {
out->push_back(soln);
}
return Status::OK();
}
for (size_t i = 0; i < relevantIndices.size(); ++i) {
LOG(2) << "Relevant index " << i << " is " << relevantIndices[i].toString() << endl;
}
// Figure out how useful each index is to each predicate.
QueryPlannerIXSelect::rateIndices(query.root(), "", relevantIndices);
QueryPlannerIXSelect::stripInvalidAssignments(query.root(), relevantIndices);
// Unless we have GEO_NEAR, TEXT, or a projection, we may be able to apply an optimization
// in which we strip unnecessary index assignments.
//
// Disallowed with projection because assignment to a non-unique index can allow the plan
// to be covered.
//
// TEXT and GEO_NEAR are special because they require the use of a text/geo index in order
// to be evaluated correctly. Stripping these "mandatory assignments" is therefore invalid.
if (query.getParsed().getProj().isEmpty() &&
!QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR) &&
!QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT)) {
QueryPlannerIXSelect::stripUnneededAssignments(query.root(), relevantIndices);
}
// query.root() is now annotated with RelevantTag(s).
LOG(5) << "Rated tree:" << endl
<< query.root()->toString();
// If there is a GEO_NEAR it must have an index it can use directly.
MatchExpression* gnNode = NULL;
if (QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR, &gnNode)) {
// No index for GEO_NEAR? No query.
RelevantTag* tag = static_cast<RelevantTag*>(gnNode->getTag());
if (0 == tag->first.size() && 0 == tag->notFirst.size()) {
LOG(5) << "Unable to find index for $geoNear query." << endl;
// Don't leave tags on query tree.
query.root()->resetTag();
return Status(ErrorCodes::BadValue, "unable to find index for $geoNear query");
}
LOG(5) << "Rated tree after geonear processing:" << query.root()->toString();
}
// Likewise, if there is a TEXT it must have an index it can use directly.
MatchExpression* textNode = NULL;
if (QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT, &textNode)) {
RelevantTag* tag = static_cast<RelevantTag*>(textNode->getTag());
// Exactly one text index required for TEXT. We need to check this explicitly because
// the text stage can't be built if no text index exists or there is an ambiguity as to
// which one to use.
size_t textIndexCount = 0;
for (size_t i = 0; i < params.indices.size(); i++) {
if (INDEX_TEXT == params.indices[i].type) {
textIndexCount++;
}
}
if (textIndexCount != 1) {
// Don't leave tags on query tree.
query.root()->resetTag();
return Status(ErrorCodes::BadValue, "need exactly one text index for $text query");
}
// Error if the text node is tagged with zero indices.
if (0 == tag->first.size() && 0 == tag->notFirst.size()) {
// Don't leave tags on query tree.
query.root()->resetTag();
return Status(ErrorCodes::BadValue,
"failed to use text index to satisfy $text query (if text index is "
"compound, are equality predicates given for all prefix fields?)");
}
// At this point, we know that there is only one text index and that the TEXT node is
// assigned to it.
invariant(1 == tag->first.size() + tag->notFirst.size());
LOG(5) << "Rated tree after text processing:" << query.root()->toString();
}
// If we have any relevant indices, we try to create indexed plans.
if (0 < relevantIndices.size()) {
// The enumerator spits out trees tagged with IndexTag(s).
PlanEnumeratorParams enumParams;
enumParams.intersect = params.options & QueryPlannerParams::INDEX_INTERSECTION;
enumParams.root = query.root();
enumParams.indices = &relevantIndices;
PlanEnumerator isp(enumParams);
isp.init();
MatchExpression* rawTree;
while (isp.getNext(&rawTree) && (out->size() < params.maxIndexedSolutions)) {
LOG(5) << "About to build solntree from tagged tree:" << endl
<< rawTree->toString();
// The tagged tree produced by the plan enumerator is not guaranteed
// to be canonically sorted. In order to be compatible with the cached
// data, sort the tagged tree according to CanonicalQuery ordering.
std::unique_ptr<MatchExpression> clone(rawTree->shallowClone());
CanonicalQuery::sortTree(clone.get());
PlanCacheIndexTree* cacheData;
Status indexTreeStatus =
cacheDataFromTaggedTree(clone.get(), relevantIndices, &cacheData);
if (!indexTreeStatus.isOK()) {
LOG(5) << "Query is not cachable: " << indexTreeStatus.reason() << endl;
}
unique_ptr<PlanCacheIndexTree> autoData(cacheData);
// This can fail if enumeration makes a mistake.
QuerySolutionNode* solnRoot = QueryPlannerAccess::buildIndexedDataAccess(
query, rawTree, false, relevantIndices, params);
if (NULL == solnRoot) {
continue;
}
QuerySolution* soln = QueryPlannerAnalysis::analyzeDataAccess(query, params, solnRoot);
if (NULL != soln) {
LOG(5) << "Planner: adding solution:" << endl
<< soln->toString();
if (indexTreeStatus.isOK()) {
SolutionCacheData* scd = new SolutionCacheData();
scd->tree.reset(autoData.release());
soln->cacheData.reset(scd);
}
out->push_back(soln);
}
}
}
// Don't leave tags on query tree.
query.root()->resetTag();
LOG(5) << "Planner: outputted " << out->size() << " indexed solutions.\n";
// Produce legible error message for failed OR planning with a TEXT child.
// TODO: support collection scan for non-TEXT children of OR.
if (out->size() == 0 && textNode != NULL && MatchExpression::OR == query.root()->matchType()) {
MatchExpression* root = query.root();
for (size_t i = 0; i < root->numChildren(); ++i) {
if (textNode == root->getChild(i)) {
return Status(ErrorCodes::BadValue,
"Failed to produce a solution for TEXT under OR - "
"other non-TEXT clauses under OR have to be indexed as well.");
}
}
}
// An index was hinted. If there are any solutions, they use the hinted index. If not, we
// scan the entire index to provide results and output that as our plan. This is the
// desired behavior when an index is hinted that is not relevant to the query.
if (!hintIndex.isEmpty()) {
if (0 == out->size()) {
QuerySolution* soln = buildWholeIXSoln(params.indices[hintIndexNumber], query, params);
verify(NULL != soln);
LOG(5) << "Planner: outputting soln that uses hinted index as scan." << endl;
out->push_back(soln);
}
return Status::OK();
}
// If a sort order is requested, there may be an index that provides it, even if that
// index is not over any predicates in the query.
//
if (!query.getParsed().getSort().isEmpty() &&
!QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR) &&
!QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT)) {
// See if we have a sort provided from an index already.
// This is implied by the presence of a non-blocking solution.
bool usingIndexToSort = false;
for (size_t i = 0; i < out->size(); ++i) {
QuerySolution* soln = (*out)[i];
if (!soln->hasBlockingStage) {
usingIndexToSort = true;
break;
}
}
if (!usingIndexToSort) {
for (size_t i = 0; i < params.indices.size(); ++i) {
const IndexEntry& index = params.indices[i];
// Only regular (non-plugin) indexes can be used to provide a sort, and only
// non-sparse indexes can be used to provide a sort.
//
// TODO: Sparse indexes can't normally provide a sort, because non-indexed
// documents could potentially be missing from the result set. However, if the
// query predicate can be used to guarantee that all documents to be returned
// are indexed, then the index should be able to provide the sort.
//
// For example:
// - Sparse index {a: 1, b: 1} should be able to provide a sort for
// find({b: 1}).sort({a: 1}). SERVER-13908.
// - Index {a: 1, b: "2dsphere"} (which is "geo-sparse", if
// 2dsphereIndexVersion=2) should be able to provide a sort for
// find({b: GEO}).sort({a:1}). SERVER-10801.
if (index.type != INDEX_BTREE) {
continue;
}
if (index.sparse) {
continue;
}
// Partial indexes can only be used to provide a sort only if the query predicate is
// compatible.
if (index.filterExpr && !expression::isSubsetOf(query.root(), index.filterExpr)) {
continue;
}
const BSONObj kp = QueryPlannerAnalysis::getSortPattern(index.keyPattern);
if (providesSort(query, kp)) {
LOG(5) << "Planner: outputting soln that uses index to provide sort." << endl;
QuerySolution* soln = buildWholeIXSoln(params.indices[i], query, params);
if (NULL != soln) {
PlanCacheIndexTree* indexTree = new PlanCacheIndexTree();
indexTree->setIndexEntry(params.indices[i]);
SolutionCacheData* scd = new SolutionCacheData();
scd->tree.reset(indexTree);
scd->solnType = SolutionCacheData::WHOLE_IXSCAN_SOLN;
scd->wholeIXSolnDir = 1;
soln->cacheData.reset(scd);
out->push_back(soln);
break;
}
}
if (providesSort(query, QueryPlannerCommon::reverseSortObj(kp))) {
LOG(5) << "Planner: outputting soln that uses (reverse) index "
<< "to provide sort." << endl;
QuerySolution* soln = buildWholeIXSoln(params.indices[i], query, params, -1);
if (NULL != soln) {
PlanCacheIndexTree* indexTree = new PlanCacheIndexTree();
indexTree->setIndexEntry(params.indices[i]);
SolutionCacheData* scd = new SolutionCacheData();
scd->tree.reset(indexTree);
scd->solnType = SolutionCacheData::WHOLE_IXSCAN_SOLN;
scd->wholeIXSolnDir = -1;
soln->cacheData.reset(scd);
out->push_back(soln);
break;
}
}
}
}
}
// geoNear and text queries *require* an index.
// Also, if a hint is specified it indicates that we MUST use it.
bool possibleToCollscan =
!QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR) &&
!QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT) && hintIndex.isEmpty();
// The caller can explicitly ask for a collscan.
bool collscanRequested = (params.options & QueryPlannerParams::INCLUDE_COLLSCAN);
// No indexed plans? We must provide a collscan if possible or else we can't run the query.
bool collscanNeeded = (0 == out->size() && canTableScan);
if (possibleToCollscan && (collscanRequested || collscanNeeded)) {
QuerySolution* collscan = buildCollscanSoln(query, false, params);
if (NULL != collscan) {
SolutionCacheData* scd = new SolutionCacheData();
scd->solnType = SolutionCacheData::COLLSCAN_SOLN;
collscan->cacheData.reset(scd);
out->push_back(collscan);
LOG(5) << "Planner: outputting a collscan:" << endl
<< collscan->toString();
}
}
return Status::OK();
}
// static
void QueryPlanner::plan(const CanonicalQuery& query,
const QueryPlannerParams& params,
vector<QuerySolution*>* out) {
QLOG() << "=============================\n"
<< "Beginning planning, options = " << optionString(params.options) << endl
<< "Canonical query:\n" << query.toString() << endl
<< "============================="
<< endl;
// The shortcut formerly known as IDHACK. See if it's a simple _id query. If so we might
// just make an ixscan over the _id index and bypass the rest of planning entirely.
if (!query.getParsed().isExplain() && !query.getParsed().showDiskLoc()
&& isSimpleIdQuery(query.getParsed().getFilter())
&& !query.getParsed().hasOption(QueryOption_CursorTailable)) {
// See if we can find an _id index.
for (size_t i = 0; i < params.indices.size(); ++i) {
if (isIdIndex(params.indices[i].keyPattern)) {
const IndexEntry& index = params.indices[i];
QLOG() << "IDHACK using index " << index.toString() << endl;
// If so, we make a simple scan to find the doc.
IndexScanNode* isn = new IndexScanNode();
isn->indexKeyPattern = index.keyPattern;
isn->indexIsMultiKey = index.multikey;
isn->direction = 1;
isn->bounds.isSimpleRange = true;
BSONObj key = getKeyFromQuery(index.keyPattern, query.getParsed().getFilter());
isn->bounds.startKey = isn->bounds.endKey = key;
isn->bounds.endKeyInclusive = true;
isn->computeProperties();
QuerySolution* soln = QueryPlannerAnalysis::analyzeDataAccess(query, params, isn);
if (NULL != soln) {
out->push_back(soln);
QLOG() << "IDHACK solution is:\n" << (*out)[0]->toString() << endl;
// And that's it.
return;
}
}
}
}
for (size_t i = 0; i < params.indices.size(); ++i) {
QLOG() << "idx " << i << " is " << params.indices[i].toString() << endl;
}
bool canTableScan = !(params.options & QueryPlannerParams::NO_TABLE_SCAN);
// If the query requests a tailable cursor, the only solution is a collscan + filter with
// tailable set on the collscan. TODO: This is a policy departure. Previously I think you
// could ask for a tailable cursor and it just tried to give you one. Now, we fail if we
// can't provide one. Is this what we want?
if (query.getParsed().hasOption(QueryOption_CursorTailable)) {
if (!QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR)
&& canTableScan) {
QuerySolution* soln = buildCollscanSoln(query, true, params);
if (NULL != soln) {
out->push_back(soln);
}
}
return;
}
// The hint can be $natural: 1. If this happens, output a collscan. It's a weird way of
// saying "table scan for two, please."
if (!query.getParsed().getHint().isEmpty()) {
BSONElement natural = query.getParsed().getHint().getFieldDotted("$natural");
if (!natural.eoo()) {
QLOG() << "forcing a table scan due to hinted $natural\n";
if (canTableScan) {
QuerySolution* soln = buildCollscanSoln(query, false, params);
if (NULL != soln) {
out->push_back(soln);
}
}
return;
}
}
// NOR and NOT we can't handle well with indices. If we see them here, they weren't
// rewritten to remove the negation. Just output a collscan for those.
if (QueryPlannerCommon::hasNode(query.root(), MatchExpression::NOT)
|| QueryPlannerCommon::hasNode(query.root(), MatchExpression::NOR)) {
// If there's a near predicate, we can't handle this.
// TODO: Should canonicalized query detect this?
if (QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR)) {
warning() << "Can't handle NOT/NOR with GEO_NEAR";
return;
}
QLOG() << "NOT/NOR in plan, just outtping a collscan\n";
if (canTableScan) {
QuerySolution* soln = buildCollscanSoln(query, false, params);
if (NULL != soln) {
out->push_back(soln);
}
}
return;
}
// Figure out what fields we care about.
unordered_set<string> fields;
QueryPlannerIXSelect::getFields(query.root(), "", &fields);
for (unordered_set<string>::const_iterator it = fields.begin(); it != fields.end(); ++it) {
QLOG() << "predicate over field " << *it << endl;
}
// Filter our indices so we only look at indices that are over our predicates.
vector<IndexEntry> relevantIndices;
// Hints require us to only consider the hinted index.
BSONObj hintIndex = query.getParsed().getHint();
// Snapshot is a form of a hint. If snapshot is set, try to use _id index to make a real
// plan. If that fails, just scan the _id index.
if (query.getParsed().isSnapshot()) {
// Find the ID index in indexKeyPatterns. It's our hint.
for (size_t i = 0; i < params.indices.size(); ++i) {
if (isIdIndex(params.indices[i].keyPattern)) {
hintIndex = params.indices[i].keyPattern;
break;
}
}
}
size_t hintIndexNumber = numeric_limits<size_t>::max();
if (!hintIndex.isEmpty()) {
// Sigh. If the hint is specified it might be using the index name.
BSONElement firstHintElt = hintIndex.firstElement();
if (str::equals("$hint", firstHintElt.fieldName()) && String == firstHintElt.type()) {
string hintName = firstHintElt.String();
for (size_t i = 0; i < params.indices.size(); ++i) {
if (params.indices[i].name == hintName) {
QLOG() << "hint by name specified, restricting indices to "
<< params.indices[i].keyPattern.toString() << endl;
relevantIndices.clear();
relevantIndices.push_back(params.indices[i]);
hintIndexNumber = i;
hintIndex = params.indices[i].keyPattern;
break;
}
}
}
else {
for (size_t i = 0; i < params.indices.size(); ++i) {
if (0 == params.indices[i].keyPattern.woCompare(hintIndex)) {
relevantIndices.clear();
relevantIndices.push_back(params.indices[i]);
QLOG() << "hint specified, restricting indices to " << hintIndex.toString()
<< endl;
hintIndexNumber = i;
break;
}
}
}
if (hintIndexNumber == numeric_limits<size_t>::max()) {
// This is supposed to be an error.
warning() << "Can't find hint for " << hintIndex.toString();
return;
}
}
else {
QLOG() << "Finding relevant indices\n";
QueryPlannerIXSelect::findRelevantIndices(fields, params.indices, &relevantIndices);
}
for (size_t i = 0; i < relevantIndices.size(); ++i) {
QLOG() << "relevant idx " << i << " is " << relevantIndices[i].toString() << endl;
}
// Figure out how useful each index is to each predicate.
// query.root() is now annotated with RelevantTag(s).
QueryPlannerIXSelect::rateIndices(query.root(), "", relevantIndices);
QLOG() << "rated tree" << endl;
QLOG() << query.root()->toString() << endl;
// If there is a GEO_NEAR it must have an index it can use directly.
// XXX: move into data access?
MatchExpression* gnNode = NULL;
if (QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR, &gnNode)) {
// No index for GEO_NEAR? No query.
RelevantTag* tag = static_cast<RelevantTag*>(gnNode->getTag());
if (0 == tag->first.size() && 0 == tag->notFirst.size()) {
return;
}
GeoNearMatchExpression* gnme = static_cast<GeoNearMatchExpression*>(gnNode);
vector<size_t> newFirst;
// 2d + GEO_NEAR is annoying. Because 2d's GEO_NEAR isn't streaming we have to embed
// the full query tree inside it as a matcher.
for (size_t i = 0; i < tag->first.size(); ++i) {
// GEO_NEAR has a non-2d index it can use. We can deal w/that in normal planning.
if (!is2DIndex(relevantIndices[tag->first[i]].keyPattern)) {
newFirst.push_back(i);
continue;
}
// If we're here, GEO_NEAR has a 2d index. We create a 2dgeonear plan with the
// entire tree as a filter, if possible.
GeoNear2DNode* solnRoot = new GeoNear2DNode();
solnRoot->nq = gnme->getData();
if (MatchExpression::GEO_NEAR != query.root()->matchType()) {
// root is an AND, clone and delete the GEO_NEAR child.
MatchExpression* filterTree = query.root()->shallowClone();
verify(MatchExpression::AND == filterTree->matchType());
bool foundChild = false;
for (size_t i = 0; i < filterTree->numChildren(); ++i) {
if (MatchExpression::GEO_NEAR == filterTree->getChild(i)->matchType()) {
foundChild = true;
filterTree->getChildVector()->erase(filterTree->getChildVector()->begin() + i);
break;
}
}
verify(foundChild);
solnRoot->filter.reset(filterTree);
}
solnRoot->numWanted = query.getParsed().getNumToReturn();
if (0 == solnRoot->numWanted) {
solnRoot->numWanted = 100;
}
solnRoot->indexKeyPattern = relevantIndices[tag->first[i]].keyPattern;
// Remove the 2d index. 2d can only be the first field, and we know there is
// only one GEO_NEAR, so we don't care if anyone else was assigned it; it'll
// only be first for gnNode.
tag->first.erase(tag->first.begin() + i);
QuerySolution* soln = QueryPlannerAnalysis::analyzeDataAccess(query, params, solnRoot);
if (NULL != soln) {
out->push_back(soln);
}
}
// Continue planning w/non-2d indices tagged for this pred.
tag->first.swap(newFirst);
if (0 == tag->first.size() && 0 == tag->notFirst.size()) {
return;
}
}
// Likewise, if there is a TEXT it must have an index it can use directly.
MatchExpression* textNode;
if (QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT, &textNode)) {
RelevantTag* tag = static_cast<RelevantTag*>(textNode->getTag());
if (0 == tag->first.size() && 0 == tag->notFirst.size()) {
return;
}
}
// If we have any relevant indices, we try to create indexed plans.
if (0 < relevantIndices.size()) {
// The enumerator spits out trees tagged with IndexTag(s).
PlanEnumerator isp(query.root(), &relevantIndices);
isp.init();
MatchExpression* rawTree;
while (isp.getNext(&rawTree)) {
QLOG() << "about to build solntree from tagged tree:\n" << rawTree->toString()
<< endl;
// This can fail if enumeration makes a mistake.
QuerySolutionNode* solnRoot =
QueryPlannerAccess::buildIndexedDataAccess(query, rawTree, false, relevantIndices);
if (NULL == solnRoot) { continue; }
QuerySolution* soln = QueryPlannerAnalysis::analyzeDataAccess(query, params, solnRoot);
if (NULL != soln) {
QLOG() << "Planner: adding solution:\n" << soln->toString() << endl;
out->push_back(soln);
}
}
}
QLOG() << "Planner: outputted " << out->size() << " indexed solutions.\n";
// An index was hinted. If there are any solutions, they use the hinted index. If not, we
// scan the entire index to provide results and output that as our plan. This is the
// desired behavior when an index is hinted that is not relevant to the query.
if (!hintIndex.isEmpty() && (0 == out->size())) {
QuerySolution* soln = buildWholeIXSoln(params.indices[hintIndexNumber], query, params);
if (NULL != soln) {
QLOG() << "Planner: outputting soln that uses hinted index as scan." << endl;
out->push_back(soln);
}
return;
}
// If a sort order is requested, there may be an index that provides it, even if that
// index is not over any predicates in the query.
//
// XXX XXX: Can we do this even if the index is sparse? Might we miss things?
if (!query.getParsed().getSort().isEmpty()
&& !QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR)
&& !QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT)) {
// See if we have a sort provided from an index already.
bool usingIndexToSort = false;
for (size_t i = 0; i < out->size(); ++i) {
QuerySolution* soln = (*out)[i];
if (!soln->hasSortStage) {
usingIndexToSort = true;
break;
}
}
if (!usingIndexToSort) {
for (size_t i = 0; i < params.indices.size(); ++i) {
const BSONObj& kp = params.indices[i].keyPattern;
if (providesSort(query, kp)) {
QLOG() << "Planner: outputting soln that uses index to provide sort."
<< endl;
QuerySolution* soln = buildWholeIXSoln(params.indices[i], query, params);
if (NULL != soln) {
out->push_back(soln);
break;
}
}
if (providesSort(query, QueryPlannerCommon::reverseSortObj(kp))) {
QLOG() << "Planner: outputting soln that uses (reverse) index "
<< "to provide sort." << endl;
QuerySolution* soln = buildWholeIXSoln(params.indices[i], query, params, -1);
if (NULL != soln) {
out->push_back(soln);
break;
}
}
}
}
}
// TODO: Do we always want to offer a collscan solution?
// XXX: currently disabling the always-use-a-collscan in order to find more planner bugs.
if ( !QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR)
&& !QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT)
&& ((params.options & QueryPlannerParams::INCLUDE_COLLSCAN) || (0 == out->size() && canTableScan)))
{
QuerySolution* collscan = buildCollscanSoln(query, false, params);
if (NULL != collscan) {
out->push_back(collscan);
QLOG() << "Planner: outputting a collscan:\n";
QLOG() << collscan->toString() << endl;
}
}
}
Status UpdateDriver::populateDocumentWithQueryFields(const CanonicalQuery* query,
mutablebson::Document& doc) const {
MatchExpression* root = query->root();
MatchExpression::MatchType rootType = root->matchType();
// These copies are needed until we apply the modifiers at the end.
std::vector<BSONObj> copies;
// We only care about equality and "and"ed equality fields, everything else is ignored
if (rootType != MatchExpression::EQ && rootType != MatchExpression::AND)
return Status::OK();
if (isDocReplacement()) {
BSONElement idElem = query->getQueryObj().getField("_id");
// Replacement mods need the _id field copied explicitly.
if (idElem.ok()) {
mb::Element elem = doc.makeElement(idElem);
return doc.root().pushFront(elem);
}
return Status::OK();
}
// Create a new UpdateDriver to create the base doc from the query
Options opts;
opts.logOp = false;
opts.multi = false;
opts.upsert = true;
opts.modOptions = modOptions();
UpdateDriver insertDriver(opts);
insertDriver.setContext(ModifierInterface::ExecInfo::INSERT_CONTEXT);
// If we are a single equality match query
if (root->matchType() == MatchExpression::EQ) {
EqualityMatchExpression* eqMatch =
static_cast<EqualityMatchExpression*>(root);
const BSONElement matchData = eqMatch->getData();
BSONElement childElem = matchData;
// Make copy to new path if not the same field name (for cases like $all)
if (!root->path().empty() && matchData.fieldNameStringData() != root->path()) {
BSONObjBuilder copyBuilder;
copyBuilder.appendAs(eqMatch->getData(), root->path());
const BSONObj copy = copyBuilder.obj();
copies.push_back(copy);
childElem = copy[root->path()];
}
// Add this element as a $set modifier
Status s = insertDriver.addAndParse(modifiertable::MOD_SET,
childElem);
if (!s.isOK())
return s;
}
else {
// parse query $set mods, including only equality stuff
for (size_t i = 0; i < root->numChildren(); ++i) {
MatchExpression* child = root->getChild(i);
if (child->matchType() == MatchExpression::EQ) {
EqualityMatchExpression* eqMatch =
static_cast<EqualityMatchExpression*>(child);
const BSONElement matchData = eqMatch->getData();
BSONElement childElem = matchData;
// Make copy to new path if not the same field name (for cases like $all)
if (!child->path().empty() &&
matchData.fieldNameStringData() != child->path()) {
BSONObjBuilder copyBuilder;
copyBuilder.appendAs(eqMatch->getData(), child->path());
const BSONObj copy = copyBuilder.obj();
copies.push_back(copy);
childElem = copy[child->path()];
}
// Add this element as a $set modifier
Status s = insertDriver.addAndParse(modifiertable::MOD_SET,
childElem);
if (!s.isOK())
return s;
}
}
}
// update the document with base field
Status s = insertDriver.update(StringData(), &doc);
copies.clear();
if (!s.isOK()) {
return Status(ErrorCodes::UnsupportedFormat,
str::stream() << "Cannot create base during"
" insert of update. Caused by :"
<< s.toString());
}
return Status::OK();
}
// static
Status QueryPlanner::plan(const CanonicalQuery& query,
const QueryPlannerParams& params,
std::vector<QuerySolution*>* out) {
QLOG() << "=============================\n"
<< "Beginning planning, options = " << optionString(params.options) << endl
<< "Canonical query:\n" << query.toString() << endl
<< "============================="
<< endl;
for (size_t i = 0; i < params.indices.size(); ++i) {
QLOG() << "idx " << i << " is " << params.indices[i].toString() << endl;
}
bool canTableScan = !(params.options & QueryPlannerParams::NO_TABLE_SCAN);
// If the query requests a tailable cursor, the only solution is a collscan + filter with
// tailable set on the collscan. TODO: This is a policy departure. Previously I think you
// could ask for a tailable cursor and it just tried to give you one. Now, we fail if we
// can't provide one. Is this what we want?
if (query.getParsed().hasOption(QueryOption_CursorTailable)) {
if (!QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR)
&& canTableScan) {
QuerySolution* soln = buildCollscanSoln(query, true, params);
if (NULL != soln) {
out->push_back(soln);
}
}
return Status::OK();
}
// The hint can be $natural: 1. If this happens, output a collscan. It's a weird way of
// saying "table scan for two, please."
if (!query.getParsed().getHint().isEmpty()) {
BSONElement natural = query.getParsed().getHint().getFieldDotted("$natural");
if (!natural.eoo()) {
QLOG() << "forcing a table scan due to hinted $natural\n";
// min/max are incompatible with $natural.
if (canTableScan && query.getParsed().getMin().isEmpty()
&& query.getParsed().getMax().isEmpty()) {
QuerySolution* soln = buildCollscanSoln(query, false, params);
if (NULL != soln) {
out->push_back(soln);
}
}
return Status::OK();
}
}
// Figure out what fields we care about.
unordered_set<string> fields;
QueryPlannerIXSelect::getFields(query.root(), "", &fields);
for (unordered_set<string>::const_iterator it = fields.begin(); it != fields.end(); ++it) {
QLOG() << "predicate over field " << *it << endl;
}
// Filter our indices so we only look at indices that are over our predicates.
vector<IndexEntry> relevantIndices;
// Hints require us to only consider the hinted index.
BSONObj hintIndex = query.getParsed().getHint();
// Snapshot is a form of a hint. If snapshot is set, try to use _id index to make a real
// plan. If that fails, just scan the _id index.
if (query.getParsed().isSnapshot()) {
// Find the ID index in indexKeyPatterns. It's our hint.
for (size_t i = 0; i < params.indices.size(); ++i) {
if (isIdIndex(params.indices[i].keyPattern)) {
hintIndex = params.indices[i].keyPattern;
break;
}
}
}
size_t hintIndexNumber = numeric_limits<size_t>::max();
if (hintIndex.isEmpty()) {
QueryPlannerIXSelect::findRelevantIndices(fields, params.indices, &relevantIndices);
}
else {
// Sigh. If the hint is specified it might be using the index name.
BSONElement firstHintElt = hintIndex.firstElement();
if (str::equals("$hint", firstHintElt.fieldName()) && String == firstHintElt.type()) {
string hintName = firstHintElt.String();
for (size_t i = 0; i < params.indices.size(); ++i) {
if (params.indices[i].name == hintName) {
QLOG() << "hint by name specified, restricting indices to "
<< params.indices[i].keyPattern.toString() << endl;
relevantIndices.clear();
relevantIndices.push_back(params.indices[i]);
hintIndexNumber = i;
hintIndex = params.indices[i].keyPattern;
break;
}
}
}
else {
for (size_t i = 0; i < params.indices.size(); ++i) {
if (0 == params.indices[i].keyPattern.woCompare(hintIndex)) {
relevantIndices.clear();
relevantIndices.push_back(params.indices[i]);
QLOG() << "hint specified, restricting indices to " << hintIndex.toString()
<< endl;
hintIndexNumber = i;
break;
}
}
}
if (hintIndexNumber == numeric_limits<size_t>::max()) {
return Status(ErrorCodes::BadValue, "bad hint");
}
}
// Deal with the .min() and .max() query options. If either exist we can only use an index
// that matches the object inside.
if (!query.getParsed().getMin().isEmpty() || !query.getParsed().getMax().isEmpty()) {
BSONObj minObj = query.getParsed().getMin();
BSONObj maxObj = query.getParsed().getMax();
// This is the index into params.indices[...] that we use.
size_t idxNo = numeric_limits<size_t>::max();
// If there's an index hinted we need to be able to use it.
if (!hintIndex.isEmpty()) {
if (!minObj.isEmpty() && !indexCompatibleMaxMin(minObj, hintIndex)) {
QLOG() << "minobj doesnt work w hint";
return Status(ErrorCodes::BadValue,
"hint provided does not work with min query");
}
if (!maxObj.isEmpty() && !indexCompatibleMaxMin(maxObj, hintIndex)) {
QLOG() << "maxobj doesnt work w hint";
return Status(ErrorCodes::BadValue,
"hint provided does not work with max query");
}
idxNo = hintIndexNumber;
}
else {
// No hinted index, look for one that is compatible (has same field names and
// ordering thereof).
for (size_t i = 0; i < params.indices.size(); ++i) {
const BSONObj& kp = params.indices[i].keyPattern;
BSONObj toUse = minObj.isEmpty() ? maxObj : minObj;
if (indexCompatibleMaxMin(toUse, kp)) {
idxNo = i;
break;
}
}
}
if (idxNo == numeric_limits<size_t>::max()) {
QLOG() << "Can't find relevant index to use for max/min query";
// Can't find an index to use, bail out.
return Status(ErrorCodes::BadValue,
"unable to find relevant index for max/min query");
}
// maxObj can be empty; the index scan just goes until the end. minObj can't be empty
// though, so if it is, we make a minKey object.
if (minObj.isEmpty()) {
BSONObjBuilder bob;
bob.appendMinKey("");
minObj = bob.obj();
}
else {
// Must strip off the field names to make an index key.
minObj = stripFieldNames(minObj);
}
if (!maxObj.isEmpty()) {
// Must strip off the field names to make an index key.
maxObj = stripFieldNames(maxObj);
}
QLOG() << "max/min query using index " << params.indices[idxNo].toString() << endl;
// Make our scan and output.
QuerySolutionNode* solnRoot = QueryPlannerAccess::makeIndexScan(params.indices[idxNo],
query,
params,
minObj,
maxObj);
QuerySolution* soln = QueryPlannerAnalysis::analyzeDataAccess(query, params, solnRoot);
if (NULL != soln) {
out->push_back(soln);
}
return Status::OK();
}
for (size_t i = 0; i < relevantIndices.size(); ++i) {
QLOG() << "relevant idx " << i << " is " << relevantIndices[i].toString() << endl;
}
// Figure out how useful each index is to each predicate.
// query.root() is now annotated with RelevantTag(s).
QueryPlannerIXSelect::rateIndices(query.root(), "", relevantIndices);
QLOG() << "rated tree" << endl;
QLOG() << query.root()->toString() << endl;
// If there is a GEO_NEAR it must have an index it can use directly.
// XXX: move into data access?
MatchExpression* gnNode = NULL;
if (QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR, &gnNode)) {
// No index for GEO_NEAR? No query.
RelevantTag* tag = static_cast<RelevantTag*>(gnNode->getTag());
if (0 == tag->first.size() && 0 == tag->notFirst.size()) {
QLOG() << "unable to find index for $geoNear query" << endl;
return Status(ErrorCodes::BadValue, "unable to find index for $geoNear query");
}
GeoNearMatchExpression* gnme = static_cast<GeoNearMatchExpression*>(gnNode);
vector<size_t> newFirst;
// 2d + GEO_NEAR is annoying. Because 2d's GEO_NEAR isn't streaming we have to embed
// the full query tree inside it as a matcher.
for (size_t i = 0; i < tag->first.size(); ++i) {
// GEO_NEAR has a non-2d index it can use. We can deal w/that in normal planning.
if (!is2DIndex(relevantIndices[tag->first[i]].keyPattern)) {
newFirst.push_back(i);
continue;
}
// If we're here, GEO_NEAR has a 2d index. We create a 2dgeonear plan with the
// entire tree as a filter, if possible.
GeoNear2DNode* solnRoot = new GeoNear2DNode();
solnRoot->nq = gnme->getData();
if (NULL != query.getProj()) {
solnRoot->addPointMeta = query.getProj()->wantGeoNearPoint();
solnRoot->addDistMeta = query.getProj()->wantGeoNearDistance();
}
if (MatchExpression::GEO_NEAR != query.root()->matchType()) {
// root is an AND, clone and delete the GEO_NEAR child.
MatchExpression* filterTree = query.root()->shallowClone();
verify(MatchExpression::AND == filterTree->matchType());
bool foundChild = false;
for (size_t i = 0; i < filterTree->numChildren(); ++i) {
if (MatchExpression::GEO_NEAR == filterTree->getChild(i)->matchType()) {
foundChild = true;
filterTree->getChildVector()->erase(filterTree->getChildVector()->begin() + i);
break;
}
}
verify(foundChild);
solnRoot->filter.reset(filterTree);
}
solnRoot->numWanted = query.getParsed().getNumToReturn();
if (0 == solnRoot->numWanted) {
solnRoot->numWanted = 100;
}
solnRoot->indexKeyPattern = relevantIndices[tag->first[i]].keyPattern;
// Remove the 2d index. 2d can only be the first field, and we know there is
// only one GEO_NEAR, so we don't care if anyone else was assigned it; it'll
// only be first for gnNode.
tag->first.erase(tag->first.begin() + i);
QuerySolution* soln = QueryPlannerAnalysis::analyzeDataAccess(query, params, solnRoot);
if (NULL != soln) {
out->push_back(soln);
}
}
// Continue planning w/non-2d indices tagged for this pred.
tag->first.swap(newFirst);
if (0 == tag->first.size() && 0 == tag->notFirst.size()) {
return Status::OK();
}
}
// Likewise, if there is a TEXT it must have an index it can use directly.
MatchExpression* textNode;
if (QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT, &textNode)) {
RelevantTag* tag = static_cast<RelevantTag*>(textNode->getTag());
if (0 == tag->first.size() && 0 == tag->notFirst.size()) {
return Status::OK();
}
}
// If we have any relevant indices, we try to create indexed plans.
if (0 < relevantIndices.size()) {
// The enumerator spits out trees tagged with IndexTag(s).
PlanEnumeratorParams enumParams;
enumParams.intersect = params.options & QueryPlannerParams::INDEX_INTERSECTION;
enumParams.root = query.root();
enumParams.indices = &relevantIndices;
PlanEnumerator isp(enumParams);
isp.init();
MatchExpression* rawTree;
// XXX: have limit on # of indexed solns we'll consider. We could have a perverse
// query and index that could make n^2 very unpleasant.
while (isp.getNext(&rawTree)) {
QLOG() << "about to build solntree from tagged tree:\n" << rawTree->toString()
<< endl;
// This can fail if enumeration makes a mistake.
QuerySolutionNode* solnRoot =
QueryPlannerAccess::buildIndexedDataAccess(query, rawTree, false, relevantIndices);
if (NULL == solnRoot) { continue; }
QuerySolution* soln = QueryPlannerAnalysis::analyzeDataAccess(query, params, solnRoot);
if (NULL != soln) {
QLOG() << "Planner: adding solution:\n" << soln->toString() << endl;
out->push_back(soln);
}
}
}
QLOG() << "Planner: outputted " << out->size() << " indexed solutions.\n";
// An index was hinted. If there are any solutions, they use the hinted index. If not, we
// scan the entire index to provide results and output that as our plan. This is the
// desired behavior when an index is hinted that is not relevant to the query.
if (!hintIndex.isEmpty()) {
if (0 == out->size()) {
QuerySolution* soln = buildWholeIXSoln(params.indices[hintIndexNumber], query, params);
verify(NULL != soln);
QLOG() << "Planner: outputting soln that uses hinted index as scan." << endl;
out->push_back(soln);
}
return Status::OK();
}
// If a sort order is requested, there may be an index that provides it, even if that
// index is not over any predicates in the query.
//
if (!query.getParsed().getSort().isEmpty()
&& !QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR)
&& !QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT)) {
// See if we have a sort provided from an index already.
bool usingIndexToSort = false;
for (size_t i = 0; i < out->size(); ++i) {
QuerySolution* soln = (*out)[i];
if (!soln->hasSortStage) {
usingIndexToSort = true;
break;
}
}
if (!usingIndexToSort) {
for (size_t i = 0; i < params.indices.size(); ++i) {
const IndexEntry& index = params.indices[i];
if (index.sparse) {
continue;
}
const BSONObj kp = LiteParsedQuery::normalizeSortOrder(index.keyPattern);
if (providesSort(query, kp)) {
QLOG() << "Planner: outputting soln that uses index to provide sort."
<< endl;
QuerySolution* soln = buildWholeIXSoln(params.indices[i], query, params);
if (NULL != soln) {
out->push_back(soln);
break;
}
}
if (providesSort(query, QueryPlannerCommon::reverseSortObj(kp))) {
QLOG() << "Planner: outputting soln that uses (reverse) index "
<< "to provide sort." << endl;
QuerySolution* soln = buildWholeIXSoln(params.indices[i], query, params, -1);
if (NULL != soln) {
out->push_back(soln);
break;
}
}
}
}
}
// TODO: Do we always want to offer a collscan solution?
// XXX: currently disabling the always-use-a-collscan in order to find more planner bugs.
if ( !QueryPlannerCommon::hasNode(query.root(), MatchExpression::GEO_NEAR)
&& !QueryPlannerCommon::hasNode(query.root(), MatchExpression::TEXT)
&& hintIndex.isEmpty()
&& ((params.options & QueryPlannerParams::INCLUDE_COLLSCAN) || (0 == out->size() && canTableScan)))
{
QuerySolution* collscan = buildCollscanSoln(query, false, params);
if (NULL != collscan) {
out->push_back(collscan);
QLOG() << "Planner: outputting a collscan:\n";
QLOG() << collscan->toString() << endl;
}
}
return Status::OK();
}