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arangodb/arangod/Indexes/Index.cpp

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////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
/// http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Jan Steemann
////////////////////////////////////////////////////////////////////////////////
#include "Aql/Ast.h"
#include "Aql/AstNode.h"
#include "Aql/Variable.h"
#include "Basics/Exceptions.h"
#include "Basics/HashSet.h"
#include "Basics/StaticStrings.h"
#include "Basics/StringUtils.h"
#include "Basics/VelocyPackHelper.h"
#include "Basics/datetime.h"
#include "Cluster/ServerState.h"
#include "Index.h"
#include "IResearch/IResearchCommon.h"
#include "StorageEngine/EngineSelectorFeature.h"
#include "StorageEngine/StorageEngine.h"
#include "VocBase/LogicalCollection.h"
#include "VocBase/ticks.h"
#include <date/date.h>
#include <velocypack/Iterator.h>
#include <velocypack/StringRef.h>
#include <velocypack/velocypack-aliases.h>
#include <iostream>
using namespace arangodb;
using namespace std::chrono;
using namespace date;
namespace {
/// @brief the _key attribute, which, when used in an index, will implictly make it unique
/// (note that we must not refer to StaticStrings::KeyString here to avoid an init-order-fiasco
std::vector<arangodb::basics::AttributeName> const KeyAttribute{
arangodb::basics::AttributeName("_key", false)};
bool hasExpansion(std::vector<std::vector<arangodb::basics::AttributeName>> const& fields) {
for (auto const& it : fields) {
if (TRI_AttributeNamesHaveExpansion(it)) {
return true;
}
}
return false;
}
/// @brief set fields from slice
std::vector<std::vector<arangodb::basics::AttributeName>> parseFields(VPackSlice const& fields,
bool allowExpansion) {
std::vector<std::vector<arangodb::basics::AttributeName>> result;
if (!fields.isArray()) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_ARANGO_ATTRIBUTE_PARSER_FAILED,
"invalid index description");
}
size_t const n = static_cast<size_t>(fields.length());
result.reserve(n);
for (auto const& name : VPackArrayIterator(fields)) {
if (!name.isString()) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_ARANGO_ATTRIBUTE_PARSER_FAILED,
"invalid index description");
}
std::vector<arangodb::basics::AttributeName> parsedAttributes;
TRI_ParseAttributeString(name.copyString(), parsedAttributes, allowExpansion);
result.emplace_back(std::move(parsedAttributes));
}
return result;
}
bool canBeNull(arangodb::aql::AstNode const* op, arangodb::aql::AstNode const* access,
std::unordered_set<std::string> const& nonNullAttributes) {
TRI_ASSERT(op != nullptr);
TRI_ASSERT(access != nullptr);
if (access->type == arangodb::aql::NODE_TYPE_ATTRIBUTE_ACCESS &&
access->getMemberUnchecked(0)->type == arangodb::aql::NODE_TYPE_REFERENCE) {
// a.b
// now check if the accessed attribute is _key, _rev or _id.
// all of these cannot be null
auto attributeName = access->getStringRef();
if (attributeName == StaticStrings::KeyString || attributeName == StaticStrings::IdString ||
attributeName == StaticStrings::RevString) {
return false;
}
}
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_LT ||
op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_LE ||
op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_EQ) {
if (op->getExcludesNull()) {
// already proven that the attribute cannot become "null"
return false;
}
}
try {
if (nonNullAttributes.find(access->toString()) != nonNullAttributes.end()) {
// found an attribute marked as non-null
return false;
}
} catch (...) {
// stringification may throw
}
// for everything else we are unsure
return true;
}
void markAsNonNull(arangodb::aql::AstNode const* op, arangodb::aql::AstNode const* access,
std::unordered_set<std::string>& nonNullAttributes) {
TRI_ASSERT(op != nullptr);
TRI_ASSERT(access != nullptr);
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_LT ||
op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_LE ||
op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_EQ) {
// non-null marking currently only supported for these node types
const_cast<arangodb::aql::AstNode*>(op)->setExcludesNull(true);
}
// all other node types will be ignored here
try {
nonNullAttributes.emplace(access->toString());
} catch (...) {
// stringification may throw
}
}
bool typeMatch(char const* type, size_t len, char const* expected) {
return (len == ::strlen(expected)) && (::memcmp(type, expected, len) == 0);
}
std::string defaultIndexName(VPackSlice const& slice) {
auto type =
arangodb::Index::type(slice.get(arangodb::StaticStrings::IndexType).copyString());
if (type == arangodb::Index::IndexType::TRI_IDX_TYPE_PRIMARY_INDEX) {
return arangodb::StaticStrings::IndexNamePrimary;
} else if (type == arangodb::Index::IndexType::TRI_IDX_TYPE_EDGE_INDEX) {
if (EngineSelectorFeature::isRocksDB()) {
auto fields = slice.get(arangodb::StaticStrings::IndexFields);
TRI_ASSERT(fields.isArray());
auto firstField = fields.at(0);
TRI_ASSERT(firstField.isString());
bool isFromIndex = firstField.isEqualString(arangodb::StaticStrings::FromString);
return isFromIndex ? arangodb::StaticStrings::IndexNameEdgeFrom
: arangodb::StaticStrings::IndexNameEdgeTo;
}
return arangodb::StaticStrings::IndexNameEdge;
}
std::string idString = arangodb::basics::VelocyPackHelper::getStringValue(
slice, arangodb::StaticStrings::IndexId.c_str(),
std::to_string(TRI_NewTickServer()));
return std::string("idx_").append(idString);
}
} // namespace
Index::FilterCosts Index::FilterCosts::zeroCosts() {
Index::FilterCosts costs;
costs.supportsCondition = true;
costs.coveredAttributes = 0;
costs.estimatedItems = 0;
costs.estimatedCosts = 0;
return costs;
}
Index::FilterCosts Index::FilterCosts::defaultCosts(size_t itemsInIndex) {
Index::FilterCosts costs;
costs.supportsCondition = false;
costs.coveredAttributes = 0;
costs.estimatedItems = itemsInIndex;
costs.estimatedCosts = static_cast<double>(itemsInIndex);
return costs;
}
Index::SortCosts Index::SortCosts::zeroCosts(size_t coveredAttributes) {
Index::SortCosts costs;
costs.coveredAttributes = coveredAttributes;
costs.supportsCondition = true;
costs.estimatedCosts = 0;
return costs;
}
Index::SortCosts Index::SortCosts::defaultCosts(size_t itemsInIndex, bool isPersistent) {
Index::SortCosts costs;
TRI_ASSERT(!costs.supportsCondition);
costs.coveredAttributes = 0;
costs.estimatedCosts = itemsInIndex > 0 ? (itemsInIndex * std::log2(static_cast<double>(itemsInIndex))) : 0.0;
if (isPersistent) {
// slightly penalize this type of index against other indexes which
// are in memory
costs.estimatedCosts *= 1.05;
}
return costs;
}
// If the Index is on a coordinator instance the index may not access the
// logical collection because it could be gone!
Index::Index(TRI_idx_iid_t iid, arangodb::LogicalCollection& collection,
std::string const& name,
std::vector<std::vector<arangodb::basics::AttributeName>> const& fields,
bool unique, bool sparse)
: _iid(iid),
_collection(collection),
_name(name),
_fields(fields),
_useExpansion(::hasExpansion(_fields)),
_unique(unique),
_sparse(sparse) {
// note: _collection can be a nullptr in the cluster coordinator case!!
}
Index::Index(TRI_idx_iid_t iid, arangodb::LogicalCollection& collection, VPackSlice const& slice)
: _iid(iid),
_collection(collection),
_name(arangodb::basics::VelocyPackHelper::getStringValue(
slice, arangodb::StaticStrings::IndexName, ::defaultIndexName(slice))),
_fields(::parseFields(slice.get(arangodb::StaticStrings::IndexFields),
Index::allowExpansion(Index::type(
slice.get(arangodb::StaticStrings::IndexType).copyString())))),
_useExpansion(::hasExpansion(_fields)),
_unique(arangodb::basics::VelocyPackHelper::getBooleanValue(slice, arangodb::StaticStrings::IndexUnique,
false)),
_sparse(arangodb::basics::VelocyPackHelper::getBooleanValue(slice, arangodb::StaticStrings::IndexSparse,
false)) {}
Index::~Index() {}
void Index::name(std::string const& newName) {
if (_name.empty()) {
_name = newName;
}
}
size_t Index::sortWeight(arangodb::aql::AstNode const* node) {
switch (node->type) {
case arangodb::aql::NODE_TYPE_OPERATOR_BINARY_EQ:
return 1;
case arangodb::aql::NODE_TYPE_OPERATOR_BINARY_IN:
return 2;
case arangodb::aql::NODE_TYPE_OPERATOR_BINARY_GT:
return 3;
case arangodb::aql::NODE_TYPE_OPERATOR_BINARY_GE:
return 4;
case arangodb::aql::NODE_TYPE_OPERATOR_BINARY_LT:
return 5;
case arangodb::aql::NODE_TYPE_OPERATOR_BINARY_LE:
return 6;
case arangodb::aql::NODE_TYPE_OPERATOR_BINARY_NE:
return 7;
default:
return 42; /* OPST_CIRCUS */
}
}
/// @brief validate fields from slice
void Index::validateFields(VPackSlice const& slice) {
VPackValueLength len;
const char* idxStr = slice.get(arangodb::StaticStrings::IndexType).getString(len);
auto allowExpansion = Index::allowExpansion(Index::type(idxStr, len));
auto fields = slice.get(arangodb::StaticStrings::IndexFields);
if (!fields.isArray()) {
return;
}
for (auto const& name : VPackArrayIterator(fields)) {
if (!name.isString()) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_ARANGO_ATTRIBUTE_PARSER_FAILED,
"invalid index description");
}
std::vector<arangodb::basics::AttributeName> parsedAttributes;
TRI_ParseAttributeString(name.copyString(), parsedAttributes, allowExpansion);
}
}
/// @brief return the index type based on a type name
Index::IndexType Index::type(char const* type, size_t len) {
if (::typeMatch(type, len, "primary")) {
return TRI_IDX_TYPE_PRIMARY_INDEX;
}
if (::typeMatch(type, len, "edge")) {
return TRI_IDX_TYPE_EDGE_INDEX;
}
if (::typeMatch(type, len, "hash")) {
return TRI_IDX_TYPE_HASH_INDEX;
}
if (::typeMatch(type, len, "skiplist")) {
return TRI_IDX_TYPE_SKIPLIST_INDEX;
}
if (::typeMatch(type, len, "ttl")) {
return TRI_IDX_TYPE_TTL_INDEX;
}
if (::typeMatch(type, len, "persistent") ||
::typeMatch(type, len, "rocksdb")) {
return TRI_IDX_TYPE_PERSISTENT_INDEX;
}
if (::typeMatch(type, len, "fulltext")) {
return TRI_IDX_TYPE_FULLTEXT_INDEX;
}
if (::typeMatch(type, len, "geo")) {
return TRI_IDX_TYPE_GEO_INDEX;
}
if (::typeMatch(type, len, "geo1")) {
return TRI_IDX_TYPE_GEO1_INDEX;
}
if (::typeMatch(type, len, "geo2")) {
return TRI_IDX_TYPE_GEO2_INDEX;
}
std::string const& tmp = arangodb::iresearch::DATA_SOURCE_TYPE.name();
if (::typeMatch(type, len, tmp.c_str())) {
return TRI_IDX_TYPE_IRESEARCH_LINK;
}
if (::typeMatch(type, len, "noaccess")) {
return TRI_IDX_TYPE_NO_ACCESS_INDEX;
}
return TRI_IDX_TYPE_UNKNOWN;
}
Index::IndexType Index::type(std::string const& type) {
return Index::type(type.c_str(), type.size());
}
/// @brief return the name of an index type
char const* Index::oldtypeName(Index::IndexType type) {
switch (type) {
case TRI_IDX_TYPE_PRIMARY_INDEX:
return "primary";
case TRI_IDX_TYPE_EDGE_INDEX:
return "edge";
case TRI_IDX_TYPE_HASH_INDEX:
return "hash";
case TRI_IDX_TYPE_SKIPLIST_INDEX:
return "skiplist";
case TRI_IDX_TYPE_TTL_INDEX:
return "ttl";
case TRI_IDX_TYPE_PERSISTENT_INDEX:
return "persistent";
case TRI_IDX_TYPE_FULLTEXT_INDEX:
return "fulltext";
case TRI_IDX_TYPE_GEO1_INDEX:
return "geo1";
case TRI_IDX_TYPE_GEO2_INDEX:
return "geo2";
case TRI_IDX_TYPE_GEO_INDEX:
return "geo";
case TRI_IDX_TYPE_IRESEARCH_LINK:
return arangodb::iresearch::DATA_SOURCE_TYPE.name().c_str();
case TRI_IDX_TYPE_NO_ACCESS_INDEX:
return "noaccess";
case TRI_IDX_TYPE_UNKNOWN: {
}
}
return "";
}
/// @brief validate an index id
bool Index::validateId(char const* key) {
char const* p = key;
while (1) {
char const c = *p;
if (c == '\0') {
return (p - key) > 0;
}
if (c >= '0' && c <= '9') {
++p;
continue;
}
return false;
}
}
/// @brief validate an index name
bool Index::validateName(char const* key) {
return TRI_vocbase_t::IsAllowedName(false, arangodb::velocypack::StringRef(key, strlen(key)));
}
namespace {
bool validatePrefix(char const* key, size_t* split) {
char const* p = key;
char c = *p;
// find divider
while (1) {
c = *p;
if (c == '\0') {
return false;
}
if (c == '/') {
break;
}
p++;
}
// store split position
*split = p - key;
return TRI_vocbase_t::IsAllowedName(true, arangodb::velocypack::StringRef(key, *split));
}
} // namespace
/// @brief validate an index handle (collection name + / + index id)
bool Index::validateHandle(char const* key, size_t* split) {
bool ok = validatePrefix(key, split);
// validate index id
return ok && validateId(key + *split + 1);
}
/// @brief validate an index handle (collection name + / + index name)
bool Index::validateHandleName(char const* key, size_t* split) {
bool ok = validatePrefix(key, split);
// validate index id
return ok && validateName(key + *split + 1);
}
/// @brief generate a new index id
TRI_idx_iid_t Index::generateId() { return TRI_NewTickServer(); }
/// @brief check if two index definitions share any identifiers (_id, name)
bool Index::CompareIdentifiers(velocypack::Slice const& lhs, velocypack::Slice const& rhs) {
VPackSlice lhsId = lhs.get(arangodb::StaticStrings::IndexId);
VPackSlice rhsId = rhs.get(arangodb::StaticStrings::IndexId);
if (lhsId.isString() && rhsId.isString() &&
arangodb::basics::VelocyPackHelper::equal(lhsId, rhsId, true)) {
return true;
}
VPackSlice lhsName = lhs.get(arangodb::StaticStrings::IndexName);
VPackSlice rhsName = rhs.get(arangodb::StaticStrings::IndexName);
if (lhsName.isString() && rhsName.isString() &&
arangodb::basics::VelocyPackHelper::equal(lhsName, rhsName, true)) {
return true;
}
return false;
}
/// @brief index comparator, used by the coordinator to detect if two index
/// contents are the same
bool Index::Compare(VPackSlice const& lhs, VPackSlice const& rhs) {
auto lhsType = lhs.get(arangodb::StaticStrings::IndexType);
TRI_ASSERT(lhsType.isString());
// type must be identical
if (!arangodb::basics::VelocyPackHelper::equal(lhsType, rhs.get(arangodb::StaticStrings::IndexType), false)) {
return false;
}
auto* engine = EngineSelectorFeature::ENGINE;
return engine && engine->indexFactory().factory(lhsType.copyString()).equal(lhs, rhs);
}
/// @brief return a contextual string for logging
std::string Index::context() const {
std::ostringstream result;
result << "index { id: " << id() << ", type: " << oldtypeName()
<< ", collection: " << _collection.vocbase().name() << "/"
<< _collection.name() << ", unique: " << (_unique ? "true" : "false")
<< ", fields: ";
result << "[";
for (size_t i = 0; i < _fields.size(); ++i) {
if (i > 0) {
result << ", ";
}
result << _fields[i];
}
result << "] }";
return result.str();
}
/// @brief create a VelocyPack representation of the index
/// base functionality (called from derived classes)
std::shared_ptr<VPackBuilder> Index::toVelocyPack(std::underlying_type<Index::Serialize>::type flags) const {
auto builder = std::make_shared<VPackBuilder>();
toVelocyPack(*builder, flags);
return builder;
}
/// @brief create a VelocyPack representation of the index
/// base functionality (called from derived classes)
/// note: needs an already-opened object as its input!
void Index::toVelocyPack(VPackBuilder& builder,
std::underlying_type<Index::Serialize>::type flags) const {
TRI_ASSERT(builder.isOpenObject());
builder.add(arangodb::StaticStrings::IndexId,
arangodb::velocypack::Value(std::to_string(_iid)));
builder.add(arangodb::StaticStrings::IndexType,
arangodb::velocypack::Value(oldtypeName(type())));
builder.add(arangodb::StaticStrings::IndexName, arangodb::velocypack::Value(name()));
builder.add(arangodb::velocypack::Value(arangodb::StaticStrings::IndexFields));
builder.openArray();
for (auto const& field : fields()) {
std::string fieldString;
TRI_AttributeNamesToString(field, fieldString);
builder.add(VPackValue(fieldString));
}
builder.close();
if (hasSelectivityEstimate() && Index::hasFlag(flags, Index::Serialize::Estimates)) {
builder.add("selectivityEstimate", VPackValue(selectivityEstimate()));
}
if (Index::hasFlag(flags, Index::Serialize::Figures)) {
builder.add("figures", VPackValue(VPackValueType::Object));
toVelocyPackFigures(builder);
builder.close();
}
}
/// @brief create a VelocyPack representation of the index figures
/// base functionality (called from derived classes)
std::shared_ptr<VPackBuilder> Index::toVelocyPackFigures() const {
auto builder = std::make_shared<VPackBuilder>();
builder->openObject();
toVelocyPackFigures(*builder);
builder->close();
return builder;
}
/// @brief create a VelocyPack representation of the index figures
/// base functionality (called from derived classes)
void Index::toVelocyPackFigures(VPackBuilder& builder) const {
TRI_ASSERT(builder.isOpenObject());
builder.add("memory", VPackValue(memory()));
}
/// @brief default implementation for matchesDefinition
bool Index::matchesDefinition(VPackSlice const& info) const {
TRI_ASSERT(info.isObject());
#ifdef ARANGODB_ENABLE_MAINTAINER_MODE
auto typeSlice = info.get(arangodb::StaticStrings::IndexType);
TRI_ASSERT(typeSlice.isString());
arangodb::velocypack::StringRef typeStr(typeSlice);
TRI_ASSERT(typeStr == oldtypeName());
#endif
auto value = info.get(arangodb::StaticStrings::IndexId);
if (!value.isNone()) {
// We already have an id.
if (!value.isString()) {
// Invalid ID
return false;
}
// Short circuit. If id is correct the index is identical.
arangodb::velocypack::StringRef idRef(value);
return idRef == std::to_string(_iid);
}
value = info.get(arangodb::StaticStrings::IndexFields);
if (!value.isArray()) {
return false;
}
size_t const n = static_cast<size_t>(value.length());
if (n != _fields.size()) {
return false;
}
if (_unique != arangodb::basics::VelocyPackHelper::getBooleanValue(
info, arangodb::StaticStrings::IndexUnique, false)) {
return false;
}
if (_sparse != arangodb::basics::VelocyPackHelper::getBooleanValue(
info, arangodb::StaticStrings::IndexSparse, false)) {
return false;
}
// This check takes ordering of attributes into account.
std::vector<arangodb::basics::AttributeName> translate;
for (size_t i = 0; i < n; ++i) {
translate.clear();
VPackSlice f = value.at(i);
if (!f.isString()) {
// Invalid field definition!
return false;
}
arangodb::velocypack::StringRef in(f);
TRI_ParseAttributeString(in, translate, true);
if (!arangodb::basics::AttributeName::isIdentical(_fields[i], translate, false)) {
return false;
}
}
return true;
}
/// @brief default implementation for selectivityEstimate
double Index::selectivityEstimate(arangodb::velocypack::StringRef const&) const {
if (_unique) {
return 1.0;
}
THROW_ARANGO_EXCEPTION(TRI_ERROR_NOT_IMPLEMENTED);
}
/// @brief whether or not the index is implicitly unique
/// this can be the case if the index is not declared as unique, but contains a
/// unique attribute such as _key
bool Index::implicitlyUnique() const {
if (_unique) {
// a unique index is always unique
return true;
}
if (_useExpansion) {
// when an expansion such as a[*] is used, the index may not be unique, even
// if it contains attributes that are guaranteed to be unique
return false;
}
for (auto const& it : _fields) {
// if _key is contained in the index fields definition, then the index is
// implicitly unique
if (it == KeyAttribute) {
return true;
}
}
// _key not contained
return false;
}
/// @brief default implementation for drop
Result Index::drop() {
return Result(); // do nothing
}
/// @brief default implementation for supportsFilterCondition
Index::FilterCosts Index::supportsFilterCondition(std::vector<std::shared_ptr<arangodb::Index>> const&,
arangodb::aql::AstNode const* /* node */,
arangodb::aql::Variable const* /* reference */,
size_t itemsInIndex) const {
// by default no filter conditions are supported
return Index::FilterCosts::defaultCosts(itemsInIndex);
}
/// @brief default implementation for supportsSortCondition
Index::SortCosts Index::supportsSortCondition(arangodb::aql::SortCondition const* /* sortCondition */,
arangodb::aql::Variable const* /* node */,
size_t itemsInIndex) const {
// by default no sort conditions are supported
return Index::SortCosts::defaultCosts(itemsInIndex, this->isPersistent());
}
arangodb::aql::AstNode* Index::specializeCondition(arangodb::aql::AstNode* /* node */,
arangodb::aql::Variable const* /* reference */) const {
// the default implementation should never be called
TRI_ASSERT(false);
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, std::string("no default implementation for specializeCondition. index type: ") + typeName());
}
std::unique_ptr<IndexIterator> Index::iteratorForCondition(transaction::Methods* /* trx */,
aql::AstNode const* /* node */,
aql::Variable const* /* reference */,
IndexIteratorOptions const& /* opts */) {
// the default implementation should never be called
TRI_ASSERT(false);
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, std::string("no default implementation for iteratorForCondition. index type: ") + typeName());
}
/// @brief perform some base checks for an index condition part
bool Index::canUseConditionPart(arangodb::aql::AstNode const* access,
arangodb::aql::AstNode const* other,
arangodb::aql::AstNode const* op,
arangodb::aql::Variable const* reference,
std::unordered_set<std::string>& nonNullAttributes,
bool isExecution) const {
if (_sparse) {
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_NIN) {
return false;
}
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_IN &&
(other->type == arangodb::aql::NODE_TYPE_EXPANSION ||
other->type == arangodb::aql::NODE_TYPE_ATTRIBUTE_ACCESS)) {
// value IN a.b OR value IN a.b[*]
if (!access->isConstant()) {
return false;
}
/* A sparse index will store null in Array
if (access->isNullValue()) {
return false;
}
*/
} else if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_IN &&
access->type == arangodb::aql::NODE_TYPE_EXPANSION) {
// value[*] IN a.b
if (!other->isConstant()) {
return false;
}
/* A sparse index will store null in Array
if (other->isNullValue()) {
return false;
}
*/
} else if (access->type == arangodb::aql::NODE_TYPE_ATTRIBUTE_ACCESS) {
// a.b == value OR a.b IN values
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_GT) {
// > anything also excludes "null". now note that this attribute cannot
// become null range definitely exludes the "null" value
::markAsNonNull(op, access, nonNullAttributes);
} else if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_LT ||
op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_LE) {
// < and <= are not supported with sparse indexes as this may include
// null values
if (::canBeNull(op, access, nonNullAttributes)) {
return false;
}
// range definitely exludes the "null" value
::markAsNonNull(op, access, nonNullAttributes);
}
if (other->isConstant()) {
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_NE && other->isNullValue()) {
// != null. now note that a certain attribute cannot become null
::markAsNonNull(op, access, nonNullAttributes);
return true;
} else if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_GE &&
!other->isNullValue()) {
// >= non-null. now note that a certain attribute cannot become null
::markAsNonNull(op, access, nonNullAttributes);
return true;
}
if (other->isNullValue() &&
(op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_EQ ||
op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_GE)) {
// == and >= null are not supported with sparse indexes for the same
// reason
if (::canBeNull(op, access, nonNullAttributes)) {
return false;
}
::markAsNonNull(op, access, nonNullAttributes);
return true;
}
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_IN &&
other->type == arangodb::aql::NODE_TYPE_ARRAY) {
size_t const n = other->numMembers();
for (size_t i = 0; i < n; ++i) {
if (other->getMemberUnchecked(i)->isNullValue()) {
return false;
}
}
::markAsNonNull(op, access, nonNullAttributes);
return true;
}
} else {
// !other->isConstant()
if (::canBeNull(op, access, nonNullAttributes)) {
return false;
}
// range definitely exludes the "null" value
::markAsNonNull(op, access, nonNullAttributes);
}
}
}
if (isExecution) {
// in execution phase, we do not need to check the variable usage again
return true;
}
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_NE) {
// none of the indexes can use !=, so we can exit here
// note that this function may have been called for operator !=. this is
// necessary to track the non-null attributes, e.g. attr != null, so we can
// note which attributes cannot be null and still use sparse indexes for
// these attributes
return false;
}
// test if the reference variable is contained on both sides of the expression
arangodb::HashSet<aql::Variable const*> variables;
if (op->type == arangodb::aql::NODE_TYPE_OPERATOR_BINARY_IN &&
(other->type == arangodb::aql::NODE_TYPE_EXPANSION ||
other->type == arangodb::aql::NODE_TYPE_ATTRIBUTE_ACCESS)) {
// value IN a.b OR value IN a.b[*]
arangodb::aql::Ast::getReferencedVariables(access, variables);
if (other->type == arangodb::aql::NODE_TYPE_ATTRIBUTE_ACCESS &&
variables.find(reference) != variables.end()) {
variables.clear();
arangodb::aql::Ast::getReferencedVariables(other, variables);
}
} else {
// a.b == value OR a.b IN values
if (!other->isConstant()) {
// don't look for referenced variables if we only access a
// constant value (there will be no variables then...)
arangodb::aql::Ast::getReferencedVariables(other, variables);
}
}
if (variables.find(reference) != variables.end()) {
// yes. then we cannot use an index here
return false;
}
return true;
}
/// @brief Transform the list of search slices to search values.
/// Always expects a list of lists as input.
/// Outer list represents the single lookups, inner list represents the
/// index field values.
/// This will multiply all IN entries and simply return all other
/// entries.
/// Example: Index on (a, b)
/// Input: [ [{=: 1}, {in: 2,3}], [{=:2}, {=:3}]
/// Result: [ [{=: 1}, {=: 2}],[{=:1}, {=:3}], [{=:2}, {=:3}]]
void Index::expandInSearchValues(VPackSlice const base, VPackBuilder& result) const {
TRI_ASSERT(base.isArray());
VPackArrayBuilder baseGuard(&result);
for (auto const& oneLookup : VPackArrayIterator(base)) {
TRI_ASSERT(oneLookup.isArray());
bool usesIn = false;
for (auto const& it : VPackArrayIterator(oneLookup)) {
if (it.hasKey(StaticStrings::IndexIn)) {
usesIn = true;
break;
}
}
if (!usesIn) {
// Shortcut, no multiply
// Just copy over base
result.add(oneLookup);
return;
}
std::unordered_map<size_t, std::vector<VPackSlice>> elements;
arangodb::basics::VelocyPackHelper::VPackLess<true> sorter;
size_t n = static_cast<size_t>(oneLookup.length());
for (VPackValueLength i = 0; i < n; ++i) {
VPackSlice current = oneLookup.at(i);
if (current.hasKey(StaticStrings::IndexIn)) {
VPackSlice inList = current.get(StaticStrings::IndexIn);
if (!inList.isArray()) {
// IN value is a non-array
result.clear();
result.openArray();
return;
}
TRI_ASSERT(inList.isArray());
VPackValueLength nList = inList.length();
if (nList == 0) {
// Empty Array. short circuit, no matches possible
result.clear();
result.openArray();
return;
}
std::unordered_set<VPackSlice, arangodb::basics::VelocyPackHelper::VPackHash, arangodb::basics::VelocyPackHelper::VPackEqual>
tmp(static_cast<size_t>(nList),
arangodb::basics::VelocyPackHelper::VPackHash(),
arangodb::basics::VelocyPackHelper::VPackEqual());
for (auto const& el : VPackArrayIterator(inList)) {
tmp.emplace(el);
}
auto& vector = elements[i];
vector.insert(vector.end(), tmp.begin(), tmp.end());
std::sort(vector.begin(), vector.end(), sorter);
}
}
// If there is an entry in elements for one depth it was an in,
// all of them are now unique so we simply have to multiply
size_t level = n - 1;
std::vector<size_t> positions(n, 0);
bool done = false;
while (!done) {
TRI_IF_FAILURE("Index::permutationIN") {
THROW_ARANGO_EXCEPTION(TRI_ERROR_DEBUG);
}
VPackArrayBuilder guard(&result);
for (size_t i = 0; i < n; ++i) {
auto list = elements.find(i);
if (list == elements.end()) {
// Insert
result.add(oneLookup.at(i));
} else {
VPackObjectBuilder objGuard(&result);
result.add(StaticStrings::IndexEq, list->second.at(positions[i]));
}
}
while (true) {
auto list = elements.find(level);
if (list != elements.end() && ++positions[level] < list->second.size()) {
level = n - 1;
// abort inner iteration
break;
}
positions[level] = 0;
if (level == 0) {
done = true;
break;
}
--level;
}
}
}
}
bool Index::covers(std::unordered_set<std::string> const& attributes) const {
// check if we can use covering indexes
if (_fields.size() < attributes.size()) {
// we will not be able to satisfy all requested projections with this index
return false;
}
std::string result;
for (size_t i = 0; i < _fields.size(); ++i) {
result.clear();
TRI_AttributeNamesToString(_fields[i], result, false);
if (std::find(attributes.begin(), attributes.end(), result) == attributes.end()) {
return false;
}
}
return true;
}
void Index::warmup(arangodb::transaction::Methods*, std::shared_ptr<basics::LocalTaskQueue>) {
// Do nothing. If an index needs some warmup
// it has to explicitly implement it.
}
/// @brief generate error message
/// @param key the conflicting key
Result& Index::addErrorMsg(Result& r, std::string const& key) {
// now provide more context based on index
r.appendErrorMessage(" - in index ");
r.appendErrorMessage(name());
r.appendErrorMessage(" of type ");
r.appendErrorMessage(oldtypeName());
// build fields string
r.appendErrorMessage(" over '");
for (size_t i = 0; i < _fields.size(); i++) {
std::string msg;
TRI_AttributeNamesToString(_fields[i], msg);
r.appendErrorMessage(msg);
if (i != _fields.size() - 1) {
r.appendErrorMessage(", ");
}
}
r.appendErrorMessage("'");
// provide conflicting key
if (!key.empty()) {
r.appendErrorMessage("; conflicting key: ");
r.appendErrorMessage(key);
}
return r;
}
/// @brief append the index description to an output stream
std::ostream& operator<<(std::ostream& stream, arangodb::Index const* index) {
stream << index->context();
return stream;
}
/// @brief append the index description to an output stream
std::ostream& operator<<(std::ostream& stream, arangodb::Index const& index) {
stream << index.context();
return stream;
}
double Index::getTimestamp(arangodb::velocypack::Slice const& doc,
std::string const& attributeName) const {
VPackSlice value = doc.get(attributeName);
if (value.isString()) {
// string value. we expect it to be YYYY-MM-DD etc.
tp_sys_clock_ms tp;
if (basics::parseDateTime(value.copyString(), tp)) {
return static_cast<double>(
std::chrono::duration_cast<std::chrono::seconds>(tp.time_since_epoch())
.count());
}
// invalid date format
// fall-through intentional
} else if (value.isNumber()) {
// numeric value. we take it as it is
return value.getNumericValue<double>();
}
// attribute not found in document, or invalid type
return -1.0;
}
/// @brief return the name of the (sole) index attribute
/// it is only allowed to call this method if the index contains a
/// single attribute
std::string const& Index::getAttribute() const {
TRI_ASSERT(_fields.size() == 1);
auto const& fields = _fields[0];
TRI_ASSERT(fields.size() == 1);
auto const& field = fields[0];
TRI_ASSERT(!field.shouldExpand);
return field.name;
}
AttributeAccessParts::AttributeAccessParts(arangodb::aql::AstNode const* comparison,
arangodb::aql::Variable const* variable)
: comparison(comparison),
attribute(nullptr),
value(nullptr),
opType(arangodb::aql::NODE_TYPE_NOP) {
// first assume a.b == value
attribute = comparison->getMember(0);
value = comparison->getMember(1);
opType = comparison->type;
if (attribute->type != arangodb::aql::NODE_TYPE_ATTRIBUTE_ACCESS) {
// got value == a.b -> flip the two sides
attribute = comparison->getMember(1);
value = comparison->getMember(0);
opType = aql::Ast::ReverseOperator(opType);
}
TRI_ASSERT(attribute->type == aql::NODE_TYPE_ATTRIBUTE_ACCESS);
TRI_ASSERT(attribute->isAttributeAccessForVariable(variable, true));
}
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