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arangodb/arangod/Aql/ExecutionPlan.cpp

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////////////////////////////////////////////////////////////////////////////////
/// @brief Aql, execution plan
///
/// @file
///
/// DISCLAIMER
///
/// Copyright 2014 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
/// @author Copyright 2014, ArangoDB GmbH, Cologne, Germany
/// @author Copyright 2012-2013, triAGENS GmbH, Cologne, Germany
////////////////////////////////////////////////////////////////////////////////
#include "ExecutionPlan.h"
#include "Aql/AggregateNode.h"
#include "Aql/AggregationOptions.h"
#include "Aql/Ast.h"
#include "Aql/AstNode.h"
#include "Aql/ExecutionNode.h"
#include "Aql/Expression.h"
#include "Aql/ModificationNodes.h"
#include "Aql/NodeFinder.h"
#include "Aql/Optimizer.h"
#include "Aql/Query.h"
#include "Aql/SortNode.h"
#include "Aql/TraversalNode.h"
#include "Aql/Variable.h"
#include "Aql/WalkerWorker.h"
#include "Basics/JsonHelper.h"
#include "Basics/Exceptions.h"
using namespace triagens::aql;
using namespace triagens::basics;
using JsonHelper = triagens::basics::JsonHelper;
// -----------------------------------------------------------------------------
// --SECTION-- constructors / destructors
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief create the plan
////////////////////////////////////////////////////////////////////////////////
ExecutionPlan::ExecutionPlan (Ast* ast)
: _ids(),
_root(nullptr),
_varUsageComputed(false),
_nextId(0),
_ast(ast),
_lastLimitNode(nullptr),
_subqueries() {
}
////////////////////////////////////////////////////////////////////////////////
/// @brief destroy the plan, frees all assigned nodes
////////////////////////////////////////////////////////////////////////////////
ExecutionPlan::~ExecutionPlan () {
for (auto& x : _ids) {
delete x.second;
}
}
// -----------------------------------------------------------------------------
// --SECTION-- public functions
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan from an AST
////////////////////////////////////////////////////////////////////////////////
ExecutionPlan* ExecutionPlan::instantiateFromAst (Ast* ast) {
TRI_ASSERT(ast != nullptr);
auto root = ast->root();
TRI_ASSERT(root != nullptr);
TRI_ASSERT(root->type == NODE_TYPE_ROOT);
std::unique_ptr<ExecutionPlan> plan(new ExecutionPlan(ast));
plan->_root = plan->fromNode(root);
// insert fullCount flag
if (plan->_lastLimitNode != nullptr && ast->query()->getBooleanOption("fullCount", false)) {
static_cast<LimitNode*>(plan->_lastLimitNode)->setFullCount();
}
plan->findVarUsage();
return plan.release();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief process the list of collections in a JSON
////////////////////////////////////////////////////////////////////////////////
void ExecutionPlan::getCollectionsFromJson (Ast* ast,
triagens::basics::Json const& json) {
TRI_ASSERT(ast != nullptr);
triagens::basics::Json jsonCollections = json.get("collections");
if (! jsonCollections.isArray()) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "json node \"collections\" not found or not an array");
}
auto const size = jsonCollections.size();
for (size_t i = 0; i < size; i++) {
triagens::basics::Json oneJsonCollection = jsonCollections.at(static_cast<int>(i));
auto typeStr = triagens::basics::JsonHelper::checkAndGetStringValue(oneJsonCollection.json(), "type");
ast->query()->collections()->add(
triagens::basics::JsonHelper::checkAndGetStringValue(oneJsonCollection.json(), "name"),
TRI_GetTransactionTypeFromStr(triagens::basics::JsonHelper::checkAndGetStringValue(oneJsonCollection.json(), "type").c_str())
);
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan from JSON
////////////////////////////////////////////////////////////////////////////////
ExecutionPlan* ExecutionPlan::instantiateFromJson (Ast* ast,
triagens::basics::Json const& json) {
TRI_ASSERT(ast != nullptr);
std::unique_ptr<ExecutionPlan> plan(new ExecutionPlan(ast));
plan->_root = plan->fromJson(json);
plan->_varUsageComputed = true;
return plan.release();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief clone the plan by recursively cloning starting from the root
////////////////////////////////////////////////////////////////////////////////
class CloneNodeAdder final : public WalkerWorker<ExecutionNode> {
ExecutionPlan* _plan;
public:
bool success;
explicit CloneNodeAdder (ExecutionPlan* plan)
: _plan(plan),
success(true) {
}
~CloneNodeAdder (){}
bool before (ExecutionNode* node) override final {
// We need to catch exceptions because the walk has to finish
// and either register the nodes or delete them.
try {
_plan->registerNode(node);
}
catch (...) {
success = false;
}
return false;
}
};
////////////////////////////////////////////////////////////////////////////////
/// @brief clone an existing execution plan
////////////////////////////////////////////////////////////////////////////////
ExecutionPlan* ExecutionPlan::clone () {
std::unique_ptr<ExecutionPlan> plan(new ExecutionPlan(_ast));
plan->_root = _root->clone(plan.get(), true, false);
plan->_nextId = _nextId;
plan->_appliedRules = _appliedRules;
CloneNodeAdder adder(plan.get());
plan->_root->walk(&adder);
if (! adder.success) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "Could not clone plan");
}
// plan->findVarUsage();
// Let's not do it here, because supposedly the plan is modified as
// the very next thing anyway!
return plan.release();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan identical to this one
/// keep the memory of the plan on the query object specified.
////////////////////////////////////////////////////////////////////////////////
ExecutionPlan* ExecutionPlan::clone (Query const& query) {
std::unique_ptr<ExecutionPlan> otherPlan(new ExecutionPlan(query.ast()));
for (auto const& it: _ids) {
otherPlan->registerNode(it.second->clone(otherPlan.get(), false, true));
}
return otherPlan.release();
}
////////////////////////////////////////////////////////////////////////////////
/// @brief export to JSON, returns an AUTOFREE Json object
////////////////////////////////////////////////////////////////////////////////
triagens::basics::Json ExecutionPlan::toJson (Ast* ast,
TRI_memory_zone_t* zone,
bool verbose) const {
triagens::basics::Json result = _root->toJson(zone, verbose);
// set up rules
auto appliedRules(std::move(Optimizer::translateRules(_appliedRules)));
triagens::basics::Json rules(triagens::basics::Json::Array, appliedRules.size());
for (auto const& r : appliedRules) {
rules.add(triagens::basics::Json(r));
}
result.set("rules", rules);
auto usedCollections = *ast->query()->collections()->collections();
triagens::basics::Json jsonCollectionList(triagens::basics::Json::Array, usedCollections.size());
for (auto const& c : usedCollections) {
triagens::basics::Json json(triagens::basics::Json::Object);
jsonCollectionList(json("name", triagens::basics::Json(c.first))
("type", triagens::basics::Json(TRI_TransactionTypeGetStr(c.second->accessType))));
}
result.set("collections", jsonCollectionList);
result.set("variables", ast->variables()->toJson(TRI_UNKNOWN_MEM_ZONE));
size_t nrItems = 0;
result.set("estimatedCost", triagens::basics::Json(_root->getCost(nrItems)));
result.set("estimatedNrItems", triagens::basics::Json(static_cast<double>(nrItems)));
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief get a list of all applied rules
////////////////////////////////////////////////////////////////////////////////
std::vector<std::string> ExecutionPlan::getAppliedRules () const {
return Optimizer::translateRules(_appliedRules);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief get a node by its id
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::getNodeById (size_t id) const {
auto it = _ids.find(id);
if (it != _ids.end()) {
// node found
return (*it).second;
}
std::string msg = std::string("node [") + std::to_string(id) + std::string("] wasn't found");
// node unknown
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, msg);
}
// -----------------------------------------------------------------------------
// --SECTION-- private methods
// -----------------------------------------------------------------------------
////////////////////////////////////////////////////////////////////////////////
/// @brief creates a calculation node for an arbitrary expression
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::createCalculation (Variable* out,
Variable const* conditionVariable,
AstNode const* expression,
ExecutionNode* previous) {
TRI_ASSERT(out != nullptr);
bool const isDistinct = (expression->type == NODE_TYPE_DISTINCT);
if (isDistinct) {
TRI_ASSERT(expression->numMembers() == 1);
expression = expression->getMember(0);
}
// generate a temporary calculation node
std::unique_ptr<Expression> expr(new Expression(_ast, const_cast<AstNode*>(expression)));
CalculationNode* en;
if (conditionVariable != nullptr) {
en = new CalculationNode(this, nextId(), expr.get(), conditionVariable, out);
}
else {
en = new CalculationNode(this, nextId(), expr.get(), out);
}
expr.release();
registerNode(reinterpret_cast<ExecutionNode*>(en));
if (previous != nullptr) {
en->addDependency(previous);
}
if (! isDistinct) {
return en;
}
// DISTINCT expression is implemented by creating an anonymous COLLECT node
auto collectNode = createAnonymousCollect(en);
collectNode->addDependency(en);
return collectNode;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief get the subquery node from an expression
/// this will return a nullptr if the expression does not refer to a subquery
////////////////////////////////////////////////////////////////////////////////
SubqueryNode* ExecutionPlan::getSubqueryFromExpression (AstNode const* expression) const {
TRI_ASSERT(expression != nullptr);
if (expression->type != NODE_TYPE_REFERENCE) {
return nullptr;
}
auto referencedVariable = static_cast<Variable const*>(expression->getData());
TRI_ASSERT(referencedVariable != nullptr);
if (referencedVariable->isUserDefined()) {
return nullptr;
}
auto it = _subqueries.find(referencedVariable->id);
if (it == _subqueries.end()) {
return nullptr;
}
return static_cast<SubqueryNode*>((*it).second);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief get the output variable from a node
////////////////////////////////////////////////////////////////////////////////
Variable const* ExecutionPlan::getOutVariable (ExecutionNode const* node) const {
if (node->getType() == ExecutionNode::CALCULATION) {
// CalculationNode has an outVariale() method
return static_cast<CalculationNode const*>(node)->outVariable();
}
if (node->getType() == ExecutionNode::AGGREGATE) {
// AggregateNode has an outVariale() method, but we cannot use it.
// for AggregateNode, outVariable() will return the variable filled by INTO,
// but INTO is an optional feature
// so this will return the first result variable of the COLLECT
// this part of the code should only be called for anonymous COLLECT nodes,
// which only have one result variable
auto en = static_cast<AggregateNode const*>(node);
auto const& vars = en->aggregateVariables();
TRI_ASSERT(vars.size() == 1);
auto v = vars[0].first;
TRI_ASSERT(v != nullptr);
return v;
}
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "invalid node type in getOutVariable");
}
////////////////////////////////////////////////////////////////////////////////
/// @brief creates an anonymous COLLECT node (for a DISTINCT)
////////////////////////////////////////////////////////////////////////////////
AggregateNode* ExecutionPlan::createAnonymousCollect (CalculationNode const* previous) {
// generate an out variable for the COLLECT
auto out = _ast->variables()->createTemporaryVariable();
TRI_ASSERT(out != nullptr);
std::vector<std::pair<Variable const*, Variable const*>> const aggregateVariables{
std::make_pair(out, previous->outVariable())
};
auto en = new AggregateNode(
this,
nextId(),
AggregationOptions(),
aggregateVariables,
nullptr,
nullptr,
std::vector<Variable const*>(),
_ast->variables()->variables(false),
false,
true
);
registerNode(reinterpret_cast<ExecutionNode*>(en));
return en;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create modification options from an AST node
////////////////////////////////////////////////////////////////////////////////
ModificationOptions ExecutionPlan::createModificationOptions (AstNode const* node) {
ModificationOptions options;
// parse the modification options we got
if (node != nullptr &&
node->type == NODE_TYPE_OBJECT) {
size_t n = node->numMembers();
for (size_t i = 0; i < n; ++i) {
auto member = node->getMember(i);
if (member != nullptr &&
member->type == NODE_TYPE_OBJECT_ELEMENT) {
auto name = member->getStringValue();
auto value = member->getMember(0);
TRI_ASSERT(value->isConstant());
if (strcmp(name, "waitForSync") == 0) {
options.waitForSync = value->isTrue();
}
else if (strcmp(name, "ignoreErrors") == 0) {
options.ignoreErrors = value->isTrue();
}
else if (strcmp(name, "keepNull") == 0) {
// nullMeansRemove is the opposite of keepNull
options.nullMeansRemove = value->isFalse();
}
else if (strcmp(name, "mergeObjects") == 0) {
options.mergeObjects = value->isTrue();
}
}
}
}
// this means a data-modification query must first read the entire input data
// before starting with the modifications
// this is safe in all cases
// the flag can be set to false later to execute read and write operations in lockstep
options.readCompleteInput = true;
if (! _ast->functionsMayAccessDocuments()) {
// no functions in the query can access document data...
bool isReadWrite = false;
if (_ast->containsTraversal()) {
// its unclear which collections the traversal will access
isReadWrite = true;
}
else {
auto const collections = _ast->query()->collections();
for (auto const& it : *(collections->collections())) {
if (it.second->isReadWrite) {
isReadWrite = true;
break;
}
}
}
if (! isReadWrite) {
// no collection is used in both read and write mode
// this means the query's write operation can use read & write in lockstep
options.readCompleteInput = false;
}
}
return options;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create COLLECT options from an AST node
////////////////////////////////////////////////////////////////////////////////
AggregationOptions ExecutionPlan::createAggregationOptions (AstNode const* node) {
AggregationOptions options;
// parse the modification options we got
if (node != nullptr &&
node->type == NODE_TYPE_OBJECT) {
size_t n = node->numMembers();
for (size_t i = 0; i < n; ++i) {
auto member = node->getMember(i);
if (member != nullptr &&
member->type == NODE_TYPE_OBJECT_ELEMENT) {
auto name = member->getStringValue();
auto value = member->getMember(0);
TRI_ASSERT(value->isConstant());
if (strcmp(name, "method") == 0) {
if (value->isStringValue()) {
options.method = AggregationOptions::methodFromString(value->getStringValue());
}
}
}
}
}
return options;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief register a node with the plan, will delete node if addition fails
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::registerNode (ExecutionNode* node) {
TRI_ASSERT(node != nullptr);
TRI_ASSERT(node->id() > 0);
try {
_ids.emplace(node->id(), node);
}
catch (...) {
delete node;
throw;
}
return node;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief creates a anonymous calculation node for an arbitrary expression
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::createTemporaryCalculation (AstNode const* expression,
ExecutionNode* previous) {
// generate a temporary variable
auto out = _ast->variables()->createTemporaryVariable();
TRI_ASSERT(out != nullptr);
return createCalculation(out, nullptr, expression, previous);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief adds "previous" as dependency to "plan", returns "plan"
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::addDependency (ExecutionNode* previous,
ExecutionNode* plan) {
TRI_ASSERT(previous != nullptr);
TRI_ASSERT(plan != nullptr);
try {
plan->addDependency(previous);
return plan;
}
catch (...) {
// prevent memleak
delete plan;
throw;
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST FOR node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeFor (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_FOR);
TRI_ASSERT(node->numMembers() == 2);
auto variable = node->getMember(0);
auto expression = node->getMember(1);
// fetch 1st operand (out variable name)
TRI_ASSERT(variable->type == NODE_TYPE_VARIABLE);
auto v = static_cast<Variable*>(variable->getData());
TRI_ASSERT(v != nullptr);
ExecutionNode* en = nullptr;
// peek at second operand
if (expression->type == NODE_TYPE_COLLECTION) {
// second operand is a collection
char const* collectionName = expression->getStringValue();
auto collections = _ast->query()->collections();
auto collection = collections->get(collectionName);
if (collection == nullptr) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "no collection for EnumerateCollection");
}
en = registerNode(new EnumerateCollectionNode(this, nextId(), _ast->query()->vocbase(), collection, v, false));
}
else if (expression->type == NODE_TYPE_REFERENCE) {
// second operand is already a variable
auto inVariable = static_cast<Variable*>(expression->getData());
TRI_ASSERT(inVariable != nullptr);
en = registerNode(new EnumerateListNode(this, nextId(), inVariable, v));
}
else {
// second operand is some misc. expression
auto calc = createTemporaryCalculation(expression, previous);
en = registerNode(new EnumerateListNode(this, nextId(), getOutVariable(calc), v));
previous = calc;
}
TRI_ASSERT(en != nullptr);
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST FOR TRAVERSAL node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeTraversal (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_TRAVERSAL);
TRI_ASSERT(node->numMembers() >= 4);
TRI_ASSERT(node->numMembers() <= 6);
// the first 3 members are used by traversal internally.
// The members 4-6, where 5 and 6 are optional, are used
// as out variables.
AstNode const* direction = node->getMember(0);
AstNode const* start = node->getMember(1);
AstNode const* graph = node->getMember(2);
// First create the node
auto travNode = new TraversalNode(this, nextId(), _ast->query()->vocbase(),
direction, start, graph);
auto variable = node->getMember(3);
TRI_ASSERT(variable->type == NODE_TYPE_VARIABLE);
auto v = static_cast<Variable*>(variable->getData());
TRI_ASSERT(v != nullptr);
travNode->setVertexOutput(v);
if (node->numMembers() > 4) {
// return the edge as well
variable = node->getMember(4);
TRI_ASSERT(variable->type == NODE_TYPE_VARIABLE);
v = static_cast<Variable*>(variable->getData());
TRI_ASSERT(v != nullptr);
travNode->setEdgeOutput(v);
if (node->numMembers() > 5) {
// return the path as well
variable = node->getMember(5);
TRI_ASSERT(variable->type == NODE_TYPE_VARIABLE);
v = static_cast<Variable*>(variable->getData());
TRI_ASSERT(v != nullptr);
travNode->setPathOutput(v);
}
}
ExecutionNode* en = registerNode(travNode);
TRI_ASSERT(en != nullptr);
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST FILTER node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeFilter (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_FILTER);
TRI_ASSERT(node->numMembers() == 1);
auto expression = node->getMember(0);
ExecutionNode* en = nullptr;
if (expression->type == NODE_TYPE_REFERENCE) {
// operand is already a variable
auto v = static_cast<Variable*>(expression->getData());
TRI_ASSERT(v != nullptr);
en = registerNode(new FilterNode(this, nextId(), v));
}
else {
// operand is some misc expression
auto calc = createTemporaryCalculation(expression, previous);
en = registerNode(new FilterNode(this, nextId(), getOutVariable(calc)));
previous = calc;
}
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST LET node
/// this also includes handling of subqueries (as subqueries can only occur
/// inside LET nodes)
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeLet (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_LET);
TRI_ASSERT(node->numMembers() >= 2);
AstNode const* variable = node->getMember(0);
AstNode const* expression = node->getMember(1);
Variable const* conditionVariable = nullptr;
if (node->numMembers() > 2) {
// a LET with an IF condition
auto condition = createTemporaryCalculation(node->getMember(2), previous);
previous = condition;
conditionVariable = getOutVariable(condition);
}
auto v = static_cast<Variable*>(variable->getData());
ExecutionNode* en = nullptr;
if (expression->type == NODE_TYPE_SUBQUERY) {
// operand is a subquery...
auto subquery = fromNode(expression);
if (subquery == nullptr) {
THROW_ARANGO_EXCEPTION(TRI_ERROR_OUT_OF_MEMORY);
}
en = registerNode(new SubqueryNode(this, nextId(), subquery, v));
_subqueries[static_cast<SubqueryNode*>(en)->outVariable()->id] = en;
}
else {
// check if the LET is a reference to a subquery
auto subquery = getSubqueryFromExpression(expression);
if (subquery != nullptr) {
// optimization: if the LET a = ... references a variable created by a subquery,
// change the output variable of the (anonymous) subquery to be the outvariable of
// the LET. and don't create the LET
subquery->replaceOutVariable(v);
return subquery;
}
// otherwise fall-through to normal behavior
// operand is some misc expression, potentially including references to other variables
return createCalculation(v, conditionVariable, expression, previous);
}
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST SORT node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeSort (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_SORT);
TRI_ASSERT(node->numMembers() == 1);
auto list = node->getMember(0);
TRI_ASSERT(list->type == NODE_TYPE_ARRAY);
std::vector<std::pair<Variable const*, bool>> elements;
std::vector<ExecutionNode*> temp;
try {
size_t const n = list->numMembers();
elements.reserve(n);
for (size_t i = 0; i < n; ++i) {
auto element = list->getMember(i);
TRI_ASSERT(element != nullptr);
TRI_ASSERT(element->type == NODE_TYPE_SORT_ELEMENT);
TRI_ASSERT(element->numMembers() == 2);
auto expression = element->getMember(0);
auto ascending = element->getMember(1);
// get sort order
bool isAscending;
bool handled = false;
if (ascending->type == NODE_TYPE_VALUE) {
if (ascending->value.type == VALUE_TYPE_STRING) {
// special treatment for string values ASC/DESC
if (TRI_CaseEqualString(ascending->value.value._string, "ASC")) {
isAscending = true;
handled = true;
}
else if (TRI_CaseEqualString(ascending->value.value._string, "DESC")) {
isAscending = false;
handled = true;
}
}
}
if (! handled) {
// if no sort order is set, ensure we have one
auto ascendingNode = ascending->castToBool(_ast);
if (ascendingNode->type == NODE_TYPE_VALUE &&
ascendingNode->value.type == VALUE_TYPE_BOOL) {
isAscending = ascendingNode->value.value._bool;
}
else {
// must have an order
isAscending = true;
}
}
if (expression->type == NODE_TYPE_REFERENCE) {
// sort operand is a variable
auto v = static_cast<Variable*>(expression->getData());
TRI_ASSERT(v != nullptr);
elements.emplace_back(std::make_pair(v, isAscending));
}
else {
// sort operand is some misc expression
auto calc = createTemporaryCalculation(expression, nullptr);
temp.emplace_back(calc);
elements.emplace_back(std::make_pair(getOutVariable(calc), isAscending));
}
}
}
catch (...) {
// prevent memleak
for (auto& it : temp) {
delete it;
}
throw;
}
if (elements.empty()) {
// no sort criterion remained - this can only happen if all sort
// criteria were constants
return previous;
}
// at least one sort criterion remained
TRI_ASSERT(! elements.empty());
// properly link the temporary calculations in the plan
for (auto it = temp.begin(); it != temp.end(); ++it) {
(*it)->addDependency(previous);
previous = (*it);
}
auto en = registerNode(new SortNode(this, nextId(), elements, false));
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST COLLECT node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeCollect (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr &&
node->type == NODE_TYPE_COLLECT);
size_t const n = node->numMembers();
TRI_ASSERT(n >= 2);
auto options = createAggregationOptions(node->getMember(0));
auto list = node->getMember(1);
size_t const numVars = list->numMembers();
std::vector<std::pair<Variable const*, Variable const*>> aggregateVariables;
aggregateVariables.reserve(numVars);
for (size_t i = 0; i < numVars; ++i) {
auto assigner = list->getMember(i);
if (assigner == nullptr) {
continue;
}
TRI_ASSERT(assigner->type == NODE_TYPE_ASSIGN);
auto out = assigner->getMember(0);
TRI_ASSERT(out != nullptr);
auto v = static_cast<Variable*>(out->getData());
TRI_ASSERT(v != nullptr);
auto expression = assigner->getMember(1);
if (expression->type == NODE_TYPE_REFERENCE) {
// operand is a variable
auto e = static_cast<Variable*>(expression->getData());
aggregateVariables.emplace_back(std::make_pair(v, e));
}
else {
// operand is some misc expression
auto calc = createTemporaryCalculation(expression, previous);
previous = calc;
aggregateVariables.emplace_back(std::make_pair(v, getOutVariable(calc)));
}
}
// handle out variable
Variable* outVariable = nullptr;
std::vector<Variable const*> keepVariables;
if (n >= 3) {
// collect with an output variable!
auto v = node->getMember(2);
outVariable = static_cast<Variable*>(v->getData());
if (n >= 4) {
auto vars = node->getMember(3);
TRI_ASSERT(vars->type == NODE_TYPE_ARRAY);
size_t const keepVarsSize = vars->numMembers();
keepVariables.reserve(keepVarsSize);
for (size_t i = 0; i < keepVarsSize; ++i) {
auto ref = vars->getMember(i);
TRI_ASSERT(ref->type == NODE_TYPE_REFERENCE);
keepVariables.emplace_back(static_cast<Variable const*>(ref->getData()));
}
}
}
auto collectNode = new AggregateNode(
this,
nextId(),
options,
aggregateVariables,
nullptr,
outVariable,
keepVariables,
_ast->variables()->variables(false),
false,
false
);
auto en = registerNode(collectNode);
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST COLLECT node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeCollectExpression (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr &&
node->type == NODE_TYPE_COLLECT_EXPRESSION);
TRI_ASSERT(node->numMembers() == 4);
auto options = createAggregationOptions(node->getMember(0));
auto list = node->getMember(1);
size_t const numVars = list->numMembers();
std::vector<std::pair<Variable const*, Variable const*>> aggregateVariables;
aggregateVariables.reserve(numVars);
for (size_t i = 0; i < numVars; ++i) {
auto assigner = list->getMember(i);
if (assigner == nullptr) {
continue;
}
TRI_ASSERT(assigner->type == NODE_TYPE_ASSIGN);
auto out = assigner->getMember(0);
TRI_ASSERT(out != nullptr);
auto v = static_cast<Variable*>(out->getData());
TRI_ASSERT(v != nullptr);
auto expression = assigner->getMember(1);
if (expression->type == NODE_TYPE_REFERENCE) {
// operand is a variable
auto e = static_cast<Variable*>(expression->getData());
aggregateVariables.emplace_back(std::make_pair(v, e));
}
else {
// operand is some misc expression
auto calc = createTemporaryCalculation(expression, previous);
previous = calc;
aggregateVariables.emplace_back(std::make_pair(v, getOutVariable(calc)));
}
}
Variable const* expressionVariable = nullptr;
auto expression = node->getMember(3);
if (expression->type == NODE_TYPE_REFERENCE) {
// expression is already a variable
auto variable = static_cast<Variable*>(expression->getData());
TRI_ASSERT(variable != nullptr);
expressionVariable = variable;
}
else {
// expression is some misc expression
auto calc = createTemporaryCalculation(expression, previous);
previous = calc;
expressionVariable = getOutVariable(calc);
}
// output variable
auto v = node->getMember(2);
Variable* outVariable = static_cast<Variable*>(v->getData());
auto collectNode = new AggregateNode(
this,
nextId(),
options,
aggregateVariables,
expressionVariable,
outVariable,
std::vector<Variable const*>(),
std::unordered_map<VariableId, std::string const>(),
false,
false
);
auto en = registerNode(collectNode);
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST COLLECT node, COUNT
/// note that also a sort plan node will be added in front of the collect plan
/// node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeCollectCount (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr &&
node->type == NODE_TYPE_COLLECT_COUNT);
TRI_ASSERT(node->numMembers() == 3);
auto options = createAggregationOptions(node->getMember(0));
auto list = node->getMember(1);
size_t const numVars = list->numMembers();
std::vector<std::pair<Variable const*, Variable const*>> aggregateVariables;
aggregateVariables.reserve(numVars);
for (size_t i = 0; i < numVars; ++i) {
auto assigner = list->getMember(i);
if (assigner == nullptr) {
continue;
}
TRI_ASSERT(assigner->type == NODE_TYPE_ASSIGN);
auto out = assigner->getMember(0);
TRI_ASSERT(out != nullptr);
auto v = static_cast<Variable*>(out->getData());
TRI_ASSERT(v != nullptr);
auto expression = assigner->getMember(1);
if (expression->type == NODE_TYPE_REFERENCE) {
// operand is a variable
auto e = static_cast<Variable*>(expression->getData());
aggregateVariables.emplace_back(std::make_pair(v, e));
}
else {
// operand is some misc expression
auto calc = createTemporaryCalculation(expression, previous);
previous = calc;
aggregateVariables.emplace_back(std::make_pair(v, getOutVariable(calc)));
}
}
// output variable
auto v = node->getMember(2);
// handle out variable
Variable* outVariable = static_cast<Variable*>(v->getData());
TRI_ASSERT(outVariable != nullptr);
auto en = registerNode(new AggregateNode(this,
nextId(),
options,
aggregateVariables,
nullptr,
outVariable,
std::vector<Variable const*>(),
_ast->variables()->variables(false),
true,
false));
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST LIMIT node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeLimit (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_LIMIT);
TRI_ASSERT(node->numMembers() == 2);
auto offset = node->getMember(0);
auto count = node->getMember(1);
TRI_ASSERT(offset->type == NODE_TYPE_VALUE);
TRI_ASSERT(count->type == NODE_TYPE_VALUE);
int64_t offsetValue = 0;
if (offset->value.type != VALUE_TYPE_NULL) {
if ((offset->value.type != VALUE_TYPE_INT &&
offset->value.type != VALUE_TYPE_DOUBLE) ||
offset->getIntValue() < 0) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_QUERY_NUMBER_OUT_OF_RANGE, "LIMIT offset value is not a number or out of range");
}
offsetValue = offset->getIntValue();
}
int64_t countValue = 128 * 1024 * 1024; // arbitrary default value for an "unbounded" limit value
if (count->value.type != VALUE_TYPE_NULL) {
if ((count->value.type != VALUE_TYPE_INT &&
count->value.type != VALUE_TYPE_DOUBLE) ||
count->getIntValue() < 0) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_QUERY_NUMBER_OUT_OF_RANGE, "LIMIT count value is not a number or out of range");
}
countValue = count->getIntValue();
}
auto en = registerNode(new LimitNode(this, nextId(), static_cast<size_t>(offsetValue), static_cast<size_t>(countValue)));
_lastLimitNode = en;
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST RETURN node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeReturn (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_RETURN);
TRI_ASSERT(node->numMembers() == 1);
auto expression = node->getMember(0);
ExecutionNode* en = nullptr;
if (expression->type == NODE_TYPE_REFERENCE) {
// operand is already a variable
auto v = static_cast<Variable*>(expression->getData());
TRI_ASSERT(v != nullptr);
en = registerNode(new ReturnNode(this, nextId(), v));
}
else {
// operand is some misc expression
auto calc = createTemporaryCalculation(expression, previous);
en = registerNode(new ReturnNode(this, nextId(), getOutVariable(calc)));
previous = calc;
}
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST REMOVE node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeRemove (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_REMOVE);
TRI_ASSERT(node->numMembers() == 4);
auto options = createModificationOptions(node->getMember(0));
char const* collectionName = node->getMember(1)->getStringValue();
auto collections = _ast->query()->collections();
auto collection = collections->get(collectionName);
if (collection == nullptr) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "no collection for RemoveNode");
}
auto expression = node->getMember(2);
ExecutionNode* en = nullptr;
auto returnVarNode = node->getMember(3);
Variable const* outVariableOld = static_cast<Variable*>(returnVarNode->getData());
if (expression->type == NODE_TYPE_REFERENCE) {
// operand is already a variable
auto v = static_cast<Variable*>(expression->getData());
TRI_ASSERT(v != nullptr);
en = registerNode(new RemoveNode(this, nextId(), _ast->query()->vocbase(), collection, options, v, outVariableOld));
}
else {
// operand is some misc expression
auto calc = createTemporaryCalculation(expression, previous);
en = registerNode(new RemoveNode(this, nextId(), _ast->query()->vocbase(), collection, options, getOutVariable(calc), outVariableOld));
previous = calc;
}
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST INSERT node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeInsert (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_INSERT);
TRI_ASSERT(node->numMembers() == 4);
auto options = createModificationOptions(node->getMember(0));
char const* collectionName = node->getMember(1)->getStringValue();
auto collections = _ast->query()->collections();
auto collection = collections->get(collectionName);
auto expression = node->getMember(2);
auto returnVarNode = node->getMember(3);
Variable const* outVariableNew = static_cast<Variable*>(returnVarNode->getData());
ExecutionNode* en = nullptr;
if (expression->type == NODE_TYPE_REFERENCE) {
// operand is already a variable
auto v = static_cast<Variable*>(expression->getData());
TRI_ASSERT(v != nullptr);
en = registerNode(new InsertNode(this, nextId(), _ast->query()->vocbase(),
collection, options, v, outVariableNew));
}
else {
// operand is some misc expression
auto calc = createTemporaryCalculation(expression, previous);
en = registerNode(new InsertNode(this, nextId(), _ast->query()->vocbase(),
collection, options, getOutVariable(calc), outVariableNew));
previous = calc;
}
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST UPDATE node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeUpdate (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_UPDATE);
TRI_ASSERT(node->numMembers() == 6);
auto options = createModificationOptions(node->getMember(0));
char const* collectionName = node->getMember(1)->getStringValue();
auto collections = _ast->query()->collections();
auto collection = collections->get(collectionName);
auto docExpression = node->getMember(2);
auto keyExpression = node->getMember(3);
Variable const* keyVariable = nullptr;
ExecutionNode* en = nullptr;
Variable const* outVariableOld = static_cast<Variable*>(node->getMember(4)->getData());
Variable const* outVariableNew = static_cast<Variable*>(node->getMember(5)->getData());
if (keyExpression->type == NODE_TYPE_NOP) {
keyExpression = nullptr;
}
if (keyExpression != nullptr) {
if (keyExpression->type == NODE_TYPE_REFERENCE) {
// key operand is already a variable
auto v = static_cast<Variable*>(keyExpression->getData());
TRI_ASSERT(v != nullptr);
keyVariable = v;
}
else {
// key operand is some misc expression
auto calc = createTemporaryCalculation(keyExpression, previous);
previous = calc;
keyVariable = getOutVariable(calc);
}
}
if (docExpression->type == NODE_TYPE_REFERENCE) {
// document operand is already a variable
auto v = static_cast<Variable*>(docExpression->getData());
TRI_ASSERT(v != nullptr);
en = registerNode(new UpdateNode(this, nextId(), _ast->query()->vocbase(),
collection, options, v,
keyVariable, outVariableOld, outVariableNew));
}
else {
// document operand is some misc expression
auto calc = createTemporaryCalculation(docExpression, previous);
en = registerNode(new UpdateNode(this, nextId(), _ast->query()->vocbase(),
collection, options, getOutVariable(calc),
keyVariable, outVariableOld, outVariableNew));
previous = calc;
}
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST REPLACE node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeReplace (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_REPLACE);
TRI_ASSERT(node->numMembers() == 6);
auto options = createModificationOptions(node->getMember(0));
char const* collectionName = node->getMember(1)->getStringValue();
auto collections = _ast->query()->collections();
auto collection = collections->get(collectionName);
auto docExpression = node->getMember(2);
auto keyExpression = node->getMember(3);
Variable const* keyVariable = nullptr;
ExecutionNode* en = nullptr;
Variable const* outVariableOld = static_cast<Variable*>(node->getMember(4)->getData());
Variable const* outVariableNew = static_cast<Variable*>(node->getMember(5)->getData());
if (keyExpression->type == NODE_TYPE_NOP) {
keyExpression = nullptr;
}
if (keyExpression != nullptr) {
if (keyExpression->type == NODE_TYPE_REFERENCE) {
// key operand is already a variable
auto v = static_cast<Variable*>(keyExpression->getData());
TRI_ASSERT(v != nullptr);
keyVariable = v;
}
else {
// key operand is some misc expression
auto calc = createTemporaryCalculation(keyExpression, previous);
previous = calc;
keyVariable = getOutVariable(calc);
}
}
if (docExpression->type == NODE_TYPE_REFERENCE) {
// operand is already a variable
auto v = static_cast<Variable*>(docExpression->getData());
TRI_ASSERT(v != nullptr);
en = registerNode(new ReplaceNode(this, nextId(), _ast->query()->vocbase(),
collection, options, v,
keyVariable, outVariableOld, outVariableNew));
}
else {
// operand is some misc expression
auto calc = createTemporaryCalculation(docExpression, previous);
en = registerNode(new ReplaceNode(this, nextId(), _ast->query()->vocbase(),
collection, options, getOutVariable(calc),
keyVariable, outVariableOld, outVariableNew));
previous = calc;
}
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan element from an AST UPSERT node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNodeUpsert (ExecutionNode* previous,
AstNode const* node) {
TRI_ASSERT(node != nullptr && node->type == NODE_TYPE_UPSERT);
TRI_ASSERT(node->numMembers() == 7);
auto options = createModificationOptions(node->getMember(0));
char const* collectionName = node->getMember(1)->getStringValue();
auto collections = _ast->query()->collections();
auto collection = collections->get(collectionName);
auto docExpression = node->getMember(2);
auto insertExpression = node->getMember(3);
auto updateExpression = node->getMember(4);
Variable const* outVariableNew = static_cast<Variable*>(node->getMember(6)->getData());
TRI_ASSERT(docExpression->type == NODE_TYPE_REFERENCE);
// doc operand is already a variable
auto docVariable = static_cast<Variable*>(docExpression->getData());
TRI_ASSERT(docVariable != nullptr);
Variable const* insertVar;
if (insertExpression->type == NODE_TYPE_REFERENCE) {
// insert operand is already a variable
insertVar = static_cast<Variable*>(insertExpression->getData());
}
else {
auto calc = createTemporaryCalculation(insertExpression, previous);
previous = calc;
insertVar = getOutVariable(calc);
}
TRI_ASSERT(insertVar != nullptr);
Variable const* updateVar;
if (updateExpression->type == NODE_TYPE_REFERENCE) {
// insert operand is already a variable
updateVar = static_cast<Variable*>(updateExpression->getData());
}
else {
auto calc = createTemporaryCalculation(updateExpression, previous);
previous = calc;
updateVar = getOutVariable(calc);
}
TRI_ASSERT(updateVar != nullptr);
bool isReplace = (node->getIntValue(true) == static_cast<int64_t>(NODE_TYPE_REPLACE));
ExecutionNode* en = registerNode(new UpsertNode(this, nextId(), _ast->query()->vocbase(),
collection, options, docVariable, insertVar, updateVar,
outVariableNew, isReplace));
return addDependency(previous, en);
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create an execution plan from an abstract syntax tree node
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromNode (AstNode const* node) {
TRI_ASSERT(node != nullptr);
ExecutionNode* en = registerNode(new SingletonNode(this, nextId()));
size_t const n = node->numMembers();
for (size_t i = 0; i < n; ++i) {
auto member = node->getMember(i);
if (member == nullptr || member->type == NODE_TYPE_NOP) {
continue;
}
switch (member->type) {
case NODE_TYPE_FOR: {
en = fromNodeFor(en, member);
break;
}
case NODE_TYPE_TRAVERSAL: {
en = fromNodeTraversal(en, member);
break;
}
case NODE_TYPE_FILTER: {
en = fromNodeFilter(en, member);
break;
}
case NODE_TYPE_LET: {
en = fromNodeLet(en, member);
break;
}
case NODE_TYPE_SORT: {
en = fromNodeSort(en, member);
break;
}
case NODE_TYPE_COLLECT: {
en = fromNodeCollect(en, member);
break;
}
case NODE_TYPE_COLLECT_EXPRESSION: {
en = fromNodeCollectExpression(en, member);
break;
}
case NODE_TYPE_COLLECT_COUNT: {
en = fromNodeCollectCount(en, member);
break;
}
case NODE_TYPE_LIMIT: {
en = fromNodeLimit(en, member);
break;
}
case NODE_TYPE_RETURN: {
en = fromNodeReturn(en, member);
break;
}
case NODE_TYPE_REMOVE: {
en = fromNodeRemove(en, member);
break;
}
case NODE_TYPE_INSERT: {
en = fromNodeInsert(en, member);
break;
}
case NODE_TYPE_UPDATE: {
en = fromNodeUpdate(en, member);
break;
}
case NODE_TYPE_REPLACE: {
en = fromNodeReplace(en, member);
break;
}
case NODE_TYPE_UPSERT: {
en = fromNodeUpsert(en, member);
break;
}
default: {
// node type not implemented
en = nullptr;
break;
}
}
if (en == nullptr) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "type not handled");
}
}
return en;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief find nodes of a certain type
////////////////////////////////////////////////////////////////////////////////
std::vector<ExecutionNode*> ExecutionPlan::findNodesOfType (ExecutionNode::NodeType type,
bool enterSubqueries) {
std::vector<ExecutionNode*> result;
NodeFinder<ExecutionNode::NodeType> finder(type, result, enterSubqueries);
root()->walk(&finder);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief find nodes of a certain types
////////////////////////////////////////////////////////////////////////////////
std::vector<ExecutionNode*> ExecutionPlan::findNodesOfType (std::vector<ExecutionNode::NodeType> const& types,
bool enterSubqueries) {
std::vector<ExecutionNode*> result;
NodeFinder<std::vector<ExecutionNode::NodeType>> finder(types, result, enterSubqueries);
root()->walk(&finder);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief find all end nodes in a plan
////////////////////////////////////////////////////////////////////////////////
std::vector<ExecutionNode*> ExecutionPlan::findEndNodes (bool enterSubqueries) const {
std::vector<ExecutionNode*> result;
EndNodeFinder finder(result, enterSubqueries);
root()->walk(&finder);
return result;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief check linkage of execution plan
////////////////////////////////////////////////////////////////////////////////
#if 0
class LinkChecker : public WalkerWorker<ExecutionNode> {
public:
LinkChecker () {
}
bool before (ExecutionNode* en) {
auto deps = en->getDependencies();
for (auto x : deps) {
auto parents = x->getParents();
bool ok = false;
for (auto it = parents.begin(); it != parents.end(); ++it) {
if (*it == en) {
ok = true;
break;
}
}
if (! ok) {
std::cout << "Found dependency which does not have us as a parent!"
<< std::endl;
}
}
auto parents = en->getParents();
if (parents.size() > 1) {
std::cout << "Found a node with more than one parent!" << std::endl;
}
for (auto x : parents) {
auto deps = x->getDependencies();
bool ok = false;
for (auto it = deps.begin(); it != deps.end(); ++it) {
if (*it == en) {
ok = true;
break;
}
}
if (! ok) {
std::cout << "Found parent which does not have us as a dependency!"
<< std::endl;
}
}
return false;
}
};
void ExecutionPlan::checkLinkage () {
LinkChecker checker;
root()->walk(&checker);
}
#endif
////////////////////////////////////////////////////////////////////////////////
/// @brief helper struct for findVarUsage
////////////////////////////////////////////////////////////////////////////////
struct VarUsageFinder final : public WalkerWorker<ExecutionNode> {
std::unordered_set<Variable const*> _usedLater;
std::unordered_set<Variable const*> _valid;
std::unordered_map<VariableId, ExecutionNode*>* _varSetBy;
bool const _ownsVarSetBy;
VarUsageFinder ()
: _varSetBy(nullptr),
_ownsVarSetBy(true) {
_varSetBy = new std::unordered_map<VariableId, ExecutionNode*>();
}
explicit VarUsageFinder (std::unordered_map<VariableId, ExecutionNode*>* varSetBy)
: _varSetBy(varSetBy),
_ownsVarSetBy(false) {
TRI_ASSERT(_varSetBy != nullptr);
}
~VarUsageFinder () {
if (_ownsVarSetBy) {
TRI_ASSERT(_varSetBy != nullptr);
delete _varSetBy;
}
}
bool before (ExecutionNode* en) override final {
en->invalidateVarUsage();
en->setVarsUsedLater(_usedLater);
// Add variables used here to _usedLater:
en->getVariablesUsedHere(_usedLater);
return false;
}
void after (ExecutionNode* en) override final {
// Add variables set here to _valid:
for (auto& v : en->getVariablesSetHere()) {
_valid.emplace(v);
_varSetBy->emplace(v->id, en);
}
en->setVarsValid(_valid);
en->setVarUsageValid();
}
bool enterSubquery (ExecutionNode*, ExecutionNode* sub) override final {
VarUsageFinder subfinder(_varSetBy);
subfinder._valid = _valid; // need a copy for the subquery!
sub->walk(&subfinder);
// we've fully processed the subquery
return false;
}
};
////////////////////////////////////////////////////////////////////////////////
/// @brief determine and set _varsUsedLater in all nodes
////////////////////////////////////////////////////////////////////////////////
void ExecutionPlan::findVarUsage () {
::VarUsageFinder finder;
root()->walk(&finder);
_varSetBy = *finder._varSetBy;
_varUsageComputed = true;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief determine if the above are already set
////////////////////////////////////////////////////////////////////////////////
bool ExecutionPlan::varUsageComputed () const {
return _varUsageComputed;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief unlinkNodes, note that this does not delete the removed
/// nodes and that one cannot remove the root node of the plan.
////////////////////////////////////////////////////////////////////////////////
void ExecutionPlan::unlinkNodes (std::unordered_set<ExecutionNode*> const& toRemove) {
for (auto& node : toRemove) {
unlinkNode(node);
}
}
////////////////////////////////////////////////////////////////////////////////
/// @brief unlinkNode, note that this does not delete the removed
/// node and that one cannot remove the root node of the plan.
////////////////////////////////////////////////////////////////////////////////
void ExecutionPlan::unlinkNode (ExecutionNode* node,
bool allowUnlinkingRoot) {
auto parents = node->getParents();
if (parents.empty()) {
if (! allowUnlinkingRoot) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL,
"Cannot unlink root node of plan");
}
// adjust root node. the caller needs to make sure that a new root node gets inserted
if (node == _root) {
_root = nullptr;
}
}
auto dep = node->getDependencies(); // Intentionally copy the vector!
for (auto* p : parents) {
p->removeDependency(node);
for (auto* x : dep) {
p->addDependency(x);
}
}
for (auto* x : dep) {
node->removeDependency(x);
}
_varUsageComputed = false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief replaceNode, note that <newNode> must be registered with the plan
/// before this method is called, also this does not delete the old
/// node and that one cannot replace the root node of the plan.
////////////////////////////////////////////////////////////////////////////////
void ExecutionPlan::replaceNode (ExecutionNode* oldNode,
ExecutionNode* newNode) {
TRI_ASSERT(oldNode->id() != newNode->id());
TRI_ASSERT(newNode->getDependencies().empty());
TRI_ASSERT(oldNode != _root);
// Intentional copy
std::vector<ExecutionNode*> deps = oldNode->getDependencies();
for (auto* x : deps) {
newNode->addDependency(x);
oldNode->removeDependency(x);
}
// Intentional copy
auto oldNodeParents = oldNode->getParents();
for (auto* oldNodeParent : oldNodeParents) {
if (! oldNodeParent->replaceDependency(oldNode, newNode)){
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL,
"Could not replace dependencies of an old node");
}
}
_varUsageComputed = false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief insert <newNode> as a new (the first!) dependency of
/// <oldNode> and make the former first dependency of <oldNode> a
/// dependency of <newNode> (and no longer a direct dependency of
/// <oldNode>).
/// <newNode> must be registered with the plan before this method is called.
////////////////////////////////////////////////////////////////////////////////
void ExecutionPlan::insertDependency (ExecutionNode* oldNode,
ExecutionNode* newNode) {
TRI_ASSERT(oldNode->id() != newNode->id());
TRI_ASSERT(newNode->getDependencies().empty());
TRI_ASSERT(oldNode->getDependencies().size() == 1);
auto oldDeps = oldNode->getDependencies(); // Intentional copy
if (! oldNode->replaceDependency(oldDeps[0], newNode)) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL,
"Could not replace dependencies of an old node");
}
newNode->removeDependencies();
newNode->addDependency(oldDeps[0]);
_varUsageComputed = false;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief create a plan from the JSON provided
////////////////////////////////////////////////////////////////////////////////
ExecutionNode* ExecutionPlan::fromJson (triagens::basics::Json const& json) {
ExecutionNode* ret = nullptr;
triagens::basics::Json nodes = json.get("nodes");
if (! nodes.isArray()) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "nodes is not an array");
}
// first, re-create all nodes from the JSON, using the node ids
// no dependency links will be set up in this step
auto const size = nodes.size();
for (size_t i = 0; i < size; i++) {
triagens::basics::Json oneJsonNode = nodes.at(static_cast<int>(i));
if (! oneJsonNode.isObject()) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "json node is not an object");
}
ret = ExecutionNode::fromJsonFactory(this, oneJsonNode);
registerNode(ret);
TRI_ASSERT(ret != nullptr);
if (ret->getType() == triagens::aql::ExecutionNode::SUBQUERY) {
// found a subquery node. now do magick here
triagens::basics::Json subquery = oneJsonNode.get("subquery");
// create the subquery nodes from the "subquery" sub-node
auto subqueryNode = fromJson(subquery);
// register the just created subquery
static_cast<SubqueryNode*>(ret)->setSubquery(subqueryNode, false);
}
}
// all nodes have been created. now add the dependencies
for (size_t i = 0; i < size; i++) {
triagens::basics::Json oneJsonNode = nodes.at(static_cast<int>(i));
if (! oneJsonNode.isObject()) {
THROW_ARANGO_EXCEPTION_MESSAGE(TRI_ERROR_INTERNAL, "json node is not an object");
}
// read the node's own id
auto thisId = triagens::basics::JsonHelper::checkAndGetNumericValue<size_t>(oneJsonNode.json(), "id");
auto thisNode = getNodeById(thisId);
// now re-link the dependencies
triagens::basics::Json dependencies = oneJsonNode.get("dependencies");
if (triagens::basics::JsonHelper::isArray(dependencies.json())) {
size_t const nDependencies = dependencies.size();
for (size_t j = 0; j < nDependencies; j ++) {
if (triagens::basics::JsonHelper::isNumber(dependencies.at(static_cast<int>(j)).json())) {
auto depId = triagens::basics::JsonHelper::getNumericValue<size_t>(dependencies.at(static_cast<int>(j)).json(), 0);
thisNode->addDependency(getNodeById(depId));
}
}
}
}
return ret;
}
////////////////////////////////////////////////////////////////////////////////
/// @brief returns true if a plan is so simple that optimizations would
/// probably cost more than simply executing the plan
////////////////////////////////////////////////////////////////////////////////
bool ExecutionPlan::isDeadSimple () const {
auto current = _root;
while (current != nullptr) {
auto const nodeType = current->getType();
if (nodeType == ExecutionNode::SUBQUERY ||
nodeType == ExecutionNode::ENUMERATE_COLLECTION ||
nodeType == ExecutionNode::ENUMERATE_LIST ||
nodeType == ExecutionNode::TRAVERSAL ||
nodeType == ExecutionNode::INDEX) {
// these node types are not simple
return false;
}
auto dep = current->getFirstDependency();
if (dep == nullptr) {
break;
}
current = dep;
}
return true;
}
#ifdef TRI_ENABLE_MAINTAINER_MODE
#include <iostream>
////////////////////////////////////////////////////////////////////////////////
/// @brief show an overview over the plan
////////////////////////////////////////////////////////////////////////////////
struct Shower final : public WalkerWorker<ExecutionNode> {
int indent;
Shower ()
: indent(0) {
}
~Shower () {
}
bool enterSubquery (ExecutionNode*, ExecutionNode*) override final {
indent++;
return true;
}
void leaveSubquery (ExecutionNode*, ExecutionNode*) override final {
indent--;
}
void after (ExecutionNode* en) override final {
for (int i = 0; i < indent; i++) {
std::cout << ' ';
}
std::cout << en->getTypeString() << std::endl;
}
};
////////////////////////////////////////////////////////////////////////////////
/// @brief show an overview over the plan
////////////////////////////////////////////////////////////////////////////////
void ExecutionPlan::show () {
Shower shower;
_root->walk(&shower);
}
#endif
// -----------------------------------------------------------------------------
// --SECTION-- END-OF-FILE
// -----------------------------------------------------------------------------
// Local Variables:
// mode: outline-minor
// outline-regexp: "/// @brief\\|/// {@inheritDoc}\\|/// @page\\|// --SECTION--\\|/// @\\}"
// End:
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