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);
}
/**
* Traverse the subtree rooted at 'node' to remove invalid RelevantTag assignments to text index
* 'idx', which has prefix paths 'prefixPaths'.
*/
static void stripInvalidAssignmentsToTextIndex(MatchExpression* node,
size_t idx,
const unordered_set<StringData, StringData::Hasher>& prefixPaths) {
// If we're here, there are prefixPaths and node is either:
// 1. a text pred which we can't use as we have nothing over its prefix, or
// 2. a non-text pred which we can't use as we don't have a text pred AND-related.
if (Indexability::nodeCanUseIndexOnOwnField(node)) {
removeIndexRelevantTag(node, idx);
return;
}
// Do not traverse tree beyond negation node.
if (node->matchType() == MatchExpression::NOT
|| node->matchType() == MatchExpression::NOR) {
return;
}
// For anything to use a text index with prefixes, we require that:
// 1. The text pred exists in an AND,
// 2. The non-text preds that use the text index's prefixes are also in that AND.
if (node->matchType() != MatchExpression::AND) {
// It's an OR or some kind of array operator.
for (size_t i = 0; i < node->numChildren(); ++i) {
stripInvalidAssignmentsToTextIndex(node->getChild(i), idx, prefixPaths);
}
return;
}
// If we're here, we're an AND. Determine whether the children satisfy the index prefix for
// the text index.
invariant(node->matchType() == MatchExpression::AND);
bool hasText = false;
// The AND must have an EQ predicate for each prefix path. When we encounter a child with a
// tag we remove it from childrenPrefixPaths. All children exist if this set is empty at
// the end.
unordered_set<StringData, StringData::Hasher> childrenPrefixPaths = prefixPaths;
for (size_t i = 0; i < node->numChildren(); ++i) {
MatchExpression* child = node->getChild(i);
RelevantTag* tag = static_cast<RelevantTag*>(child->getTag());
if (NULL == tag) {
// 'child' could be a logical operator. Maybe there are some assignments hiding
// inside.
stripInvalidAssignmentsToTextIndex(child, idx, prefixPaths);
continue;
}
bool inFirst = tag->first.end() != std::find(tag->first.begin(),
tag->first.end(),
idx);
bool inNotFirst = tag->notFirst.end() != std::find(tag->notFirst.begin(),
tag->notFirst.end(),
idx);
if (inFirst || inNotFirst) {
// Great! 'child' was assigned to our index.
if (child->matchType() == MatchExpression::TEXT) {
hasText = true;
}
else {
childrenPrefixPaths.erase(child->path());
// One fewer prefix we're looking for, possibly. Note that we could have a
// suffix assignment on the index and wind up here. In this case the erase
// above won't do anything since a suffix isn't a prefix.
}
}
else {
// Recurse on the children to ensure that they're not hiding any assignments
// to idx.
stripInvalidAssignmentsToTextIndex(child, idx, prefixPaths);
}
}
// Our prereqs for using the text index were not satisfied so we remove the assignments from
// all children of the AND.
if (!hasText || !childrenPrefixPaths.empty()) {
for (size_t i = 0; i < node->numChildren(); ++i) {
stripInvalidAssignmentsToTextIndex(node->getChild(i), idx, prefixPaths);
}
}
}
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();
}