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Avoid match full scan when has in predicate
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fix

small fix

add test case

small change

add test cases

small fix

fmt
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czpmango committed Oct 21, 2022
1 parent 3bafa14 commit ad746f5
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Showing 6 changed files with 118 additions and 17 deletions.
48 changes: 34 additions & 14 deletions src/common/expression/ContainerExpression.h
Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,9 @@
#ifndef COMMON_EXPRESSION_CONTAINEREXPRESSION_H_
#define COMMON_EXPRESSION_CONTAINEREXPRESSION_H_

#include "common/base/ObjectPool.h"
#include "common/expression/ConstantExpression.h"
#include "common/expression/ContainerExpression.h"
#include "common/expression/Expression.h"

namespace nebula {
Expand Down Expand Up @@ -63,7 +66,16 @@ class MapItemList final {
std::vector<Pair> items_;
};

class ListExpression final : public Expression {
class ContainerExpression : public Expression {
public:
virtual const std::vector<Expression *> getKeys() const = 0;
virtual size_t size() const = 0;

protected:
ContainerExpression(ObjectPool *pool, Expression::Kind kind) : Expression(pool, kind) {}
};

class ListExpression final : public ContainerExpression {
public:
ListExpression &operator=(const ListExpression &rhs) = delete;
ListExpression &operator=(ListExpression &&) = delete;
Expand All @@ -84,15 +96,15 @@ class ListExpression final : public Expression {
items_[index] = item;
}

std::vector<Expression *> get() {
const std::vector<Expression *> getKeys() const override {
return items_;
}

void setItems(std::vector<Expression *> items) {
items_ = items;
}

size_t size() const {
size_t size() const override {
return items_.size();
}

Expand All @@ -116,9 +128,9 @@ class ListExpression final : public Expression {

private:
friend ObjectPool;
explicit ListExpression(ObjectPool *pool) : Expression(pool, Kind::kList) {}
explicit ListExpression(ObjectPool *pool) : ContainerExpression(pool, Kind::kList) {}

ListExpression(ObjectPool *pool, ExpressionList *items) : Expression(pool, Kind::kList) {
ListExpression(ObjectPool *pool, ExpressionList *items) : ContainerExpression(pool, Kind::kList) {
items_ = items->get();
}

Expand All @@ -131,7 +143,7 @@ class ListExpression final : public Expression {
Value result_;
};

class SetExpression final : public Expression {
class SetExpression final : public ContainerExpression {
public:
SetExpression &operator=(const SetExpression &rhs) = delete;
SetExpression &operator=(SetExpression &&) = delete;
Expand All @@ -152,15 +164,15 @@ class SetExpression final : public Expression {
items_[index] = item;
}

std::vector<Expression *> get() {
const std::vector<Expression *> getKeys() const override {
return items_;
}

void setItems(std::vector<Expression *> items) {
items_ = items;
}

size_t size() const {
size_t size() const override {
return items_.size();
}

Expand All @@ -184,9 +196,9 @@ class SetExpression final : public Expression {

private:
friend ObjectPool;
explicit SetExpression(ObjectPool *pool) : Expression(pool, Kind::kSet) {}
explicit SetExpression(ObjectPool *pool) : ContainerExpression(pool, Kind::kSet) {}

SetExpression(ObjectPool *pool, ExpressionList *items) : Expression(pool, Kind::kSet) {
SetExpression(ObjectPool *pool, ExpressionList *items) : ContainerExpression(pool, Kind::kSet) {
items_ = items->get();
}

Expand All @@ -199,7 +211,7 @@ class SetExpression final : public Expression {
Value result_;
};

class MapExpression final : public Expression {
class MapExpression final : public ContainerExpression {
public:
MapExpression &operator=(const MapExpression &rhs) = delete;
MapExpression &operator=(MapExpression &&) = delete;
Expand Down Expand Up @@ -230,7 +242,15 @@ class MapExpression final : public Expression {
return items_;
}

size_t size() const {
const std::vector<Expression *> getKeys() const override {
std::vector<Expression *> keys;
for (const auto &item : items_) {
keys.emplace_back(ConstantExpression::make(pool_, item.first));
}
return keys;
}

size_t size() const override {
return items_.size();
}

Expand All @@ -254,9 +274,9 @@ class MapExpression final : public Expression {

private:
friend ObjectPool;
explicit MapExpression(ObjectPool *pool) : Expression(pool, Kind::kMap) {}
explicit MapExpression(ObjectPool *pool) : ContainerExpression(pool, Kind::kMap) {}

MapExpression(ObjectPool *pool, MapItemList *items) : Expression(pool, Kind::kMap) {
MapExpression(ObjectPool *pool, MapItemList *items) : ContainerExpression(pool, Kind::kMap) {
items_ = items->get();
}

Expand Down
51 changes: 49 additions & 2 deletions src/graph/util/ExpressionUtils.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -4,8 +4,11 @@

#include "graph/util/ExpressionUtils.h"

#include "ExpressionUtils.h"
#include "common/base/ObjectPool.h"
#include "common/expression/ArithmeticExpression.h"
#include "common/expression/ConstantExpression.h"
#include "common/expression/ContainerExpression.h"
#include "common/expression/Expression.h"
#include "common/expression/PropertyExpression.h"
#include "common/function/AggFunctionManager.h"
Expand Down Expand Up @@ -177,6 +180,50 @@ Expression *ExpressionUtils::rewriteParameter(const Expression *expr, QueryConte
return graph::RewriteVisitor::transform(expr, matcher, rewriter);
}

Expression *ExpressionUtils::rewriteInnerInExpr(const Expression *expr) {
auto matcher = [](const Expression *e) -> bool {
if (e->kind() != Expression::Kind::kRelIn) {
return false;
}
auto rhs = static_cast<const RelationalExpression *>(e)->right();
if (rhs->kind() != Expression::Kind::kList && rhs->kind() != Expression::Kind::kSet) {
return false;
}
auto items = static_cast<const ContainerExpression *>(rhs)->getKeys();
for (const auto *item : items) {
if (!ExpressionUtils::isEvaluableExpr(item)) {
return false;
}
}
return true;
};
auto rewriter = [](const Expression *e) -> Expression * {
DCHECK_EQ(e->kind(), Expression::Kind::kRelIn);
const auto re = static_cast<const RelationalExpression *>(e);
auto lhs = re->left();
auto rhs = re->right();
DCHECK(rhs->kind() == Expression::Kind::kList || rhs->kind() == Expression::Kind::kSet);
auto ce = static_cast<const ContainerExpression *>(rhs);
auto pool = e->getObjPool();
auto *rewrittenExpr = LogicalExpression::makeOr(pool);
// Pointer to a single-level expression
Expression *singleExpr = nullptr;
auto items = ce->getKeys();
for (auto i = 0u; i < items.size(); ++i) {
auto *ee = RelationalExpression::makeEQ(pool, lhs->clone(), items[i]->clone());
rewrittenExpr->addOperand(ee);
if (i == 0) {
singleExpr = ee;
} else {
singleExpr = nullptr;
}
}
return singleExpr ? singleExpr : rewrittenExpr;
};

return graph::RewriteVisitor::transform(expr, matcher, rewriter);
}

Expression *ExpressionUtils::rewriteAgg2VarProp(const Expression *expr) {
ObjectPool *pool = expr->getObjPool();
auto matcher = [](const Expression *e) -> bool {
Expand Down Expand Up @@ -344,10 +391,10 @@ std::vector<Expression *> ExpressionUtils::getContainerExprOperands(const Expres
std::vector<Expression *> containerOperands;
switch (containerExpr->kind()) {
case Expression::Kind::kList:
containerOperands = static_cast<ListExpression *>(containerExpr)->get();
containerOperands = static_cast<ListExpression *>(containerExpr)->getKeys();
break;
case Expression::Kind::kSet: {
containerOperands = static_cast<SetExpression *>(containerExpr)->get();
containerOperands = static_cast<SetExpression *>(containerExpr)->getKeys();
break;
}
case Expression::Kind::kMap: {
Expand Down
3 changes: 3 additions & 0 deletions src/graph/util/ExpressionUtils.h
Original file line number Diff line number Diff line change
Expand Up @@ -83,6 +83,9 @@ class ExpressionUtils {
// Rewrites ParameterExpression to ConstantExpression
static Expression* rewriteParameter(const Expression* expr, QueryContext* qctx);

// Rewrite RelInExpr with only one operand in expression tree
static Expression* rewriteInnerInExpr(const Expression* expr);

// Rewrites relational expression, gather all evaluable expressions in the left operands and move
// them to the right
static Expression* rewriteRelExpr(const Expression* expr);
Expand Down
3 changes: 2 additions & 1 deletion src/graph/validator/MatchValidator.cpp
Original file line number Diff line number Diff line change
Expand Up @@ -303,7 +303,8 @@ Status MatchValidator::buildEdgeInfo(const MatchPath *path,
// Rewrite expression to fit semantic, check type and check used aliases.
Status MatchValidator::validateFilter(const Expression *filter,
WhereClauseContext &whereClauseCtx) {
auto transformRes = ExpressionUtils::filterTransform(filter);
auto *newFilter = graph::ExpressionUtils::rewriteInnerInExpr(filter);
auto transformRes = ExpressionUtils::filterTransform(newFilter);
NG_RETURN_IF_ERROR(transformRes);
// rewrite Attribute to LabelTagProperty
whereClauseCtx.filter = ExpressionUtils::rewriteAttr2LabelTagProp(
Expand Down
29 changes: 29 additions & 0 deletions tests/tck/features/match/IndexSelecting.feature
Original file line number Diff line number Diff line change
Expand Up @@ -57,6 +57,35 @@ Feature: Index selecting for match statement
| 2 | AppendVertices | 5 | |
| 5 | IndexScan | 0 | {"indexCtx": {"columnHints":{"scanType":"PREFIX"}}} |
| 0 | Start | | |
When profiling query:
"""
MATCH (v:player) WHERE v.player.name in ["Yao Ming"] RETURN v.player.name AS name
"""
Then the result should be, in any order, with relax comparison:
| name |
| "Yao Ming" |
And the execution plan should be:
| id | name | dependencies | operator info |
| 6 | Project | 2 | |
| 2 | Filter | 5 | |
| 2 | AppendVertices | 5 | |
| 5 | IndexScan | 0 | {"indexCtx": {"columnHints":{"scanType":"PREFIX"}}} |
| 0 | Start | | |
When profiling query:
"""
MATCH (v:player) WHERE v.player.name in ["Yao Ming", "Tim Duncan"] RETURN v.player.name AS name
"""
Then the result should be, in any order, with relax comparison:
| name |
| "Tim Duncan" |
| "Yao Ming" |
And the execution plan should be:
| id | name | dependencies | operator info |
| 6 | Project | 2 | |
| 2 | Filter | 5 | |
| 2 | AppendVertices | 5 | |
| 5 | IndexScan | 0 | {"indexCtx": {"columnHints":{"scanType":"PREFIX"}}} |
| 0 | Start | | |
When profiling query:
"""
MATCH (v:player) WHERE v.player.name == "Tim Duncan" and v.player.name < "Zom" RETURN v.player.name AS name
Expand Down
1 change: 1 addition & 0 deletions tests/tck/features/match/SeekById.feature
Original file line number Diff line number Diff line change
Expand Up @@ -226,6 +226,7 @@ Feature: Match seek by id
| "Rajon Rondo" | "Lakers" |
| "LeBron James" | "Lakers" |

@czp
Scenario: can't refer
When executing query:
"""
Expand Down

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