impr

src/CMakeLists.txt

@@ -63,7 +63,7 @@ add_subdirectory (Server)
 
 
 set(dbms_headers)
-set(dbms_sources Interpreters/ConstraintMatcherVisitor.cpp Interpreters/ConstraintMatcherVisitor.h Interpreters/WhereConstraintsOptimizer.cpp Interpreters/WhereConstraintsOptimizer.h Interpreters/TreeCNFConverter.cpp Interpreters/TreeCNFConverter.h)
+set(dbms_sources Interpreters/ConstraintMatcherVisitor.cpp Interpreters/ConstraintMatcherVisitor.h Interpreters/WhereConstraintsOptimizer.cpp Interpreters/WhereConstraintsOptimizer.h Interpreters/TreeCNFConverter.cpp Interpreters/TreeCNFConverter.h Interpreters/ComparisonGraph.cpp Interpreters/ComparisonGraph.h)
 
 add_headers_and_sources(clickhouse_common_io Common)
 add_headers_and_sources(clickhouse_common_io Common/HashTable)

src/Interpreters/ComparisonGraph.cpp

@@ -0,0 +1,38 @@
+#include <Interpreters/ComparisonGraph.h>
+
+#include <algorithm>
+
+namespace DB
+{
+
+ComparisonGraph::ComparisonGraph(const std::vector<ASTPtr> & /*atomic_formulas*/)
+{
+}
+
+std::vector<ASTPtr> ComparisonGraph::getEqual(const ASTPtr & ast) const
+{
+    const auto hash_it = graph.ast_hash_to_component.find(ast->getTreeHash().second);
+    if (hash_it != std::end(graph.ast_hash_to_component))
+        return {};
+    const size_t index = hash_it->second;
+    //const auto vertex_it = std::find(std::begin(graph.vertexes[index].asts), std::end(graph.vertexes[index].asts), ast, );
+    if (std::any_of(
+            std::cbegin(graph.vertexes[index].asts),
+            std::cend(graph.vertexes[index].asts),
+            [ast](const ASTPtr & constraint_ast)
+            {
+                return constraint_ast->getTreeHash() == ast->getTreeHash() &&
+                    constraint_ast->getColumnName() == ast->getColumnName();
+            })) {
+        return graph.vertexes[index].asts;
+    } else {
+        return {};
+    }
+}
+
+ComparisonGraph::Graph ComparisonGraph::BuildGraphFromAsts(const Graph & /*asts_graph*/)
+{
+    return {};
+}
+
+}

src/Interpreters/ComparisonGraph.h

@@ -0,0 +1,76 @@
+#pragma once
+
+#include <Parsers/IAST_fwd.h>
+#include <Parsers/ASTLiteral.h>
+#include <unordered_map>
+#include <vector>
+
+namespace DB
+{
+
+class ComparisonGraph
+{
+public:
+    ComparisonGraph(const std::vector<ASTPtr> & atomic_formulas);
+
+    /// Works for string and num.
+    /// For other -- only eq.
+    enum class CompareResult
+    {
+        LESS,
+        LESS_OR_EQUAL,
+        EQUAL,
+        GREATER_OR_EQUAL,
+        GREATER,
+        //NOT_EQUAL,
+        UNKNOWN,
+    };
+
+    // TODO: implement
+    CompareResult compare(const ASTPtr & /*left*/, const ASTPtr & /*right*/) const { return CompareResult::UNKNOWN; }
+
+    std::vector<ASTPtr> getEqual(const ASTPtr & ast) const;
+
+    /// Find constants less and greater.
+    /// For int and double linear programming can be applied here.
+    // TODO: implement
+    ASTPtr getMax(const ASTPtr &) const { return nullptr; } // sup
+    ASTPtr getMin(const ASTPtr &) const { return nullptr; } // inf
+
+private:
+    /// strongly connected component
+    struct EqualComponent
+    {
+        std::vector<ASTPtr> asts;
+    };
+
+    /// TODO: move to diff for int and double:
+    /// LESS and LESS_OR_EQUAL with +const or 0 --- ok
+    ///                        with -const --- not ok
+    /// EQUAL is ok only for 0
+    struct Edge
+    {
+        enum Type
+        {
+            LESS,
+            LESS_OR_EQUAL,
+            EQUAL,
+        };
+
+        Type type;
+        EqualComponent to;
+    };
+
+    struct Graph
+    {
+        std::unordered_map<UInt64, size_t> ast_hash_to_component;
+        std::vector<EqualComponent> vertexes;
+        std::vector<std::vector<Edge>> edges;
+    };
+
+    Graph BuildGraphFromAsts(const Graph & asts_graph);
+
+    Graph graph;
+};
+
+}

src/Interpreters/TreeCNFConverter.cpp

@@ -149,9 +149,13 @@ void traverseCNF(const ASTPtr & node, CNFQuery::AndGroup & and_group, CNFQuery::
             traverseCNF(child, and_group, or_group);
         }
     }
+    else if (func && func->name == "not")
+    {
+        or_group.insert(CNFQuery::AtomicFormula{true, func->arguments->children.front()});
+    }
     else
     {
-        or_group.insert(node);
+        or_group.insert(CNFQuery::AtomicFormula{false, node});
     }
 }
 
@@ -190,13 +194,23 @@ ASTPtr TreeCNFConverter::fromCNF(const CNFQuery & cnf)
     for (const auto & group : groups)
     {
         if (group.size() == 1)
-            or_groups.push_back((*group.begin())->clone());
+        {
+            if ((*group.begin()).negative)
+                or_groups.push_back(makeASTFunction("not", (*group.begin()).ast->clone()));
+            else
+                or_groups.push_back((*group.begin()).ast->clone());
+        }
         else if (group.size() > 1)
         {
             or_groups.push_back(makeASTFunction("or"));
             auto * func = or_groups.back()->as<ASTFunction>();
-            for (const auto & ast : group)
-                func->arguments->children.push_back(ast->clone());
+            for (const auto & atom : group)
+            {
+                if ((*group.begin()).negative)
+                    func->arguments->children.push_back(makeASTFunction("not", atom.ast->clone()));
+                else
+                    func->arguments->children.push_back(atom.ast->clone());
+            }
         }
     }
 
@@ -211,7 +225,23 @@ ASTPtr TreeCNFConverter::fromCNF(const CNFQuery & cnf)
     return res;
 }
 
-void pullNotOut(ASTPtr & node)
+void pushPullNotInAtom(CNFQuery::AtomicFormula & atom, const std::map<std::string, std::string> & inverse_relations)
+{
+    auto * func = atom.ast->as<ASTFunction>();
+    if (!func)
+        return;
+    if (auto it = inverse_relations.find(func->name); it != std::end(inverse_relations))
+    {
+        /// inverse func
+        atom.ast = atom.ast->clone();
+        auto * new_func = atom.ast->as<ASTFunction>();
+        new_func->name = it->second;
+        /// add not
+        atom.negative = !atom.negative;
+    }
+}
+
+void pullNotOut(CNFQuery::AtomicFormula & atom)
 {
     static const std::map<std::string, std::string> inverse_relations = {
         {"notEquals", "equals"},
@@ -222,22 +252,14 @@ void pullNotOut(ASTPtr & node)
         {"notEmpty", "empty"},
     };
 
-    auto * func = node->as<ASTFunction>();
-    if (!func)
-        return;
-    if (auto it = inverse_relations.find(func->name); it != std::end(inverse_relations))
-    {
-        /// inverse func
-        node = node->clone();
-        auto * new_func = node->as<ASTFunction>();
-        new_func->name = it->second;
-        /// add not
-        node = makeASTFunction("not", node);
-    }
+    pushPullNotInAtom(atom, inverse_relations);
 }
 
-void pushNotIn(ASTPtr & node)
+void pushNotIn(CNFQuery::AtomicFormula & atom)
 {
+    if (!atom.negative)
+        return;
+
     static const std::map<std::string, std::string> inverse_relations = {
         {"equals", "notEquals"},
         {"less", "greaterOrEquals"},
@@ -245,35 +267,23 @@ void pushNotIn(ASTPtr & node)
         {"in", "notIn"},
         {"like", "notLike"},
         {"empty", "notEmpty"},
+        {"notEquals", "equals"},
+        {"greaterOrEquals", "less"},
+        {"greater", "lessOrEquals"},
+        {"notIn", "in"},
+        {"notLike", "like"},
+        {"notEmpty", "empty"},
     };
 
-    auto * func = node->as<ASTFunction>();
-    if (!func)
-        return;
-    if (auto it = inverse_relations.find(func->name); it != std::end(inverse_relations))
-    {
-        /// inverse func
-        node = node->clone();
-        auto * new_func = node->as<ASTFunction>();
-        new_func->name = it->second;
-        /// add not
-        node = makeASTFunction("not", node);
-    }
+    pushPullNotInAtom(atom, inverse_relations);
 }
 
 CNFQuery & CNFQuery::pullNotOutFunctions()
 {
-    transformAtoms([](const ASTPtr & node) -> ASTPtr
+    transformAtoms([](const AtomicFormula & atom) -> AtomicFormula
                     {
-                     auto * func = node->as<ASTFunction>();
-                     if (!func)
-                        return node;
-                     ASTPtr result = node->clone();
-                     if (func->name == "not")
-                         pullNotOut(func->arguments->children.front());
-                     else
+                        AtomicFormula result{atom.negative, atom.ast->clone()};
                         pullNotOut(result);
-                     traversePushNot(result, false);
                         return result;
                     });
     return *this;
@@ -281,15 +291,10 @@ CNFQuery & CNFQuery::pullNotOutFunctions()
 
 CNFQuery & CNFQuery::pushNotInFuntions()
 {
-    transformAtoms([](const ASTPtr & node) -> ASTPtr
+    transformAtoms([](const AtomicFormula & atom) -> AtomicFormula
                    {
-                       auto * func = node->as<ASTFunction>();
-                       if (!func)
-                           return node;
-                       ASTPtr result = node->clone();
-                       if (func->name == "not")
-                           pushNotIn(func->arguments->children.front());
-                       traversePushNot(result, false);
+                       AtomicFormula result{atom.negative, atom.ast->clone()};
+                       pushNotIn(result);
                        return result;
                    });
     return *this;
@@ -306,12 +311,14 @@ std::string CNFQuery::dump() const
         first = false;
         res << "(";
         bool first_in_group = true;
-        for (const auto & ast : group)
+        for (const auto & atom : group)
         {
             if (!first_in_group)
                 res << " OR ";
             first_in_group = false;
-            res << ast->getColumnName();
+            if (atom.negative)
+                res << " NOT ";
+            res << atom.ast->getColumnName();
         }
         res << ")";
     }

src/Interpreters/TreeCNFConverter.h

@@ -12,7 +12,19 @@ namespace DB
 class CNFQuery
 {
 public:
-    using OrGroup = std::set<ASTPtr>; // Add NOT container???
+    struct AtomicFormula
+    {
+        bool negative = false;
+        ASTPtr ast;
+
+        /// for set
+        bool operator<(const AtomicFormula & rhs) const
+        {
+            return ast == rhs.ast ? negative < rhs.negative : ast < rhs.ast;
+        }
+    };
+
+    using OrGroup = std::set<AtomicFormula>;
     using AndGroup = std::set<OrGroup>;
 
     CNFQuery(AndGroup && statements_) : statements(std::move(statements_)) { }
@@ -49,7 +61,7 @@ public:
                 /// all atoms false -> group false -> CNF   false
                 filtered.clear();
                 filtered_group.clear();
-                filtered_group.insert(std::make_shared<ASTLiteral>(static_cast<UInt8>(0)));
+                filtered_group.insert(AtomicFormula{false, std::make_shared<ASTLiteral>(static_cast<UInt8>(0))});
                 filtered.insert(filtered_group);
                 std::swap(statements, filtered);
                 return *this;
@@ -79,11 +91,11 @@ public:
         transformGroups([func](const OrGroup & group) -> OrGroup
                         {
                             OrGroup result;
-                            for (const auto & ast : group)
+                            for (const auto & atom : group)
                             {
-                                auto new_ast = func(ast);
-                                if (new_ast)
-                                    result.insert(std::move(new_ast));
+                                auto new_atom = func(atom);
+                                if (new_atom.ast)
+                                    result.insert(std::move(new_atom));
                             }
                             return result;
                         });

src/Interpreters/WhereConstraintsOptimizer.cpp

@@ -9,9 +9,9 @@
 
 namespace DB
 {
-std::vector<std::vector<ASTPtr>> getConstraintData(const StorageMetadataPtr & metadata_snapshot)
+std::vector<std::vector<CNFQuery::AtomicFormula>> getConstraintData(const StorageMetadataPtr & metadata_snapshot)
 {
-    std::vector<std::vector<ASTPtr>> constraint_data;
+    std::vector<std::vector<CNFQuery::AtomicFormula>> constraint_data;
     for (const auto & constraint :
          metadata_snapshot->getConstraints().filterConstraints(ConstraintsDescription::ConstraintType::ALWAYS_TRUE))
     {
@@ -24,6 +24,39 @@ std::vector<std::vector<ASTPtr>> getConstraintData(const StorageMetadataPtr & me
     return constraint_data;
 }
 
+std::vector<CNFQuery::AtomicFormula> getAtomicConstraintData(const StorageMetadataPtr & metadata_snapshot)
+{
+    std::vector<CNFQuery::AtomicFormula> constraint_data;
+    for (const auto & constraint :
+        metadata_snapshot->getConstraints().filterConstraints(ConstraintsDescription::ConstraintType::ALWAYS_TRUE))
+    {
+        const auto cnf = TreeCNFConverter::toCNF(constraint->as<ASTConstraintDeclaration>()->expr->ptr())
+            .pullNotOutFunctions(); /// TODO: move prepare stage to ConstraintsDescription
+        for (const auto & group : cnf.getStatements()) {
+            if (group.size() == 1)
+                constraint_data.push_back(*group.begin());
+        }
+    }
+
+    return constraint_data;
+}
+
+std::vector<std::pair<ASTPtr, ASTPtr>> getEqualConstraintData(const StorageMetadataPtr & metadata_snapshot)
+{
+    std::vector<std::pair<ASTPtr, ASTPtr>> equal_constraints;
+    const std::vector<CNFQuery::AtomicFormula> atomic_constraints = getAtomicConstraintData(metadata_snapshot);
+    for (const auto & constraint : atomic_constraints) {
+        auto * func = constraint.ast->as<ASTFunction>();
+        if (func && (func->name == "equal" && !constraint.negative))
+        {
+            equal_constraints.emplace_back(
+                func->arguments->children[0],
+                func->arguments->children[1]);
+        }
+    }
+    return equal_constraints;
+}
+
 WhereConstraintsOptimizer::WhereConstraintsOptimizer(
     ASTSelectQuery * select_query_,
     Aliases & /*aliases_*/,
@@ -48,37 +81,22 @@ namespace
     };
 }
 
-MatchState match(ASTPtr a, ASTPtr b)
+MatchState match(CNFQuery::AtomicFormula a, CNFQuery::AtomicFormula b)
 {
-    bool match_means_ok = true;
+    bool match_means_ok = true ^ a.negative ^ b.negative;
 
-    {
-        auto * func_a = a->as<ASTFunction>();
-        if (func_a && func_a->name == "not")
-        {
-            a = func_a->arguments->children.front();
-            match_means_ok ^= true;
-        }
-    }
-    {
-        auto * func_b = b->as<ASTFunction>();
-        if (func_b && func_b->name == "not")
-        {
-            b = func_b->arguments->children.front();
-            match_means_ok ^= true;
-        }
-    }
-
-    if (a->getTreeHash() == b->getTreeHash() &&
-        a->getColumnName() == b->getColumnName())
+    if (a.ast->getTreeHash() == b.ast->getTreeHash() &&
+        a.ast->getColumnName() == b.ast->getColumnName())
     {
         return match_means_ok ? MatchState::FULL_MATCH : MatchState::NOT_MATCH;
     }
     return MatchState::NONE;
 }
 
-bool checkIfGroupAlwaysTrue(const CNFQuery::OrGroup & group, const std::vector<std::vector<ASTPtr>> & constraints)
+bool checkIfGroupAlwaysTrue(const CNFQuery::OrGroup & group, const std::vector<std::vector<CNFQuery::AtomicFormula>> & constraints)
 {
+    /// TODO: constraints graph
+
     /// TODO: this is temporary; need to write more effective search
     /// TODO: go deeper into asts (a < b, a = b,...) with z3 or some visitor
     for (const auto & constraint : constraints) /// one constraint in group is enough,
@@ -111,7 +129,7 @@ bool checkIfGroupAlwaysTrue(const CNFQuery::OrGroup & group, const std::vector<s
     return false;
 }
 
-bool checkIfAtomAlwaysFalse(const ASTPtr & atom, const std::vector<std::vector<ASTPtr>> & constraints)
+bool checkIfAtomAlwaysFalse(const CNFQuery::AtomicFormula & atom, const std::vector<std::vector<CNFQuery::AtomicFormula>> & constraints)
 {
     /// TODO: more efficient matching
 
@@ -120,9 +138,9 @@ bool checkIfAtomAlwaysFalse(const ASTPtr & atom, const std::vector<std::vector<A
         if (constraint.size() > 1)
             continue; /// TMP
 
-        for (const auto & constraint_ast : constraint)
+        for (const auto & constraint_atoms : constraint)
         {
-            const auto match_result = match(constraint_ast, atom);
+            const auto match_result = match(constraint_atoms, atom);
 
             if (match_result != MatchState::NONE)
                 return match_result == MatchState::NOT_MATCH;
@@ -137,14 +155,15 @@ void WhereConstraintsOptimizer::perform()
     if (select_query->where() && metadata_snapshot)
     {
         const auto constraint_data = getConstraintData(metadata_snapshot);
+        Poco::Logger::get("BEFORE CNF ").information(select_query->where()->dumpTree());
         auto cnf = TreeCNFConverter::toCNF(select_query->where());
         Poco::Logger::get("BEFORE OPT").information(cnf.dump());
         cnf.pullNotOutFunctions()
             .filterAlwaysTrueGroups([&constraint_data](const auto & group) { /// remove always true groups from CNF
                 return !checkIfGroupAlwaysTrue(group, constraint_data);
             })
-            .filterAlwaysFalseAtoms([&constraint_data](const auto & ast) { /// remove always false atoms from CNF
-                return !checkIfAtomAlwaysFalse(ast, constraint_data);
+            .filterAlwaysFalseAtoms([&constraint_data](const auto & atom) { /// remove always false atoms from CNF
+                return !checkIfAtomAlwaysFalse(atom, constraint_data);
             })
             .pushNotInFuntions();
 

src/Storages/ConstraintsDescription.h

@@ -2,6 +2,7 @@
 
 #include <Parsers/ASTConstraintDeclaration.h>
 #include <Interpreters/ExpressionActions.h>
+#include <Interpreters/TreeCNFConverter.h>
 
 namespace DB
 {
@@ -11,6 +12,7 @@ using ConstraintsExpressions = std::vector<ExpressionActionsPtr>;
 struct ConstraintsDescription
 {
     std::vector<ASTPtr> constraints;
+    std::vector<CNFQuery> cnf_constraints;
 
     ConstraintsDescription() = default;
 
@@ -27,6 +29,9 @@ struct ConstraintsDescription
     };
 
     ASTs filterConstraints(ConstraintType selection) const;
+    // TODO: перенести преобразование в КНФ + get constraitns
+    //ASTs filterAtomicConstraints(ConstraintType selection) const;
+    //ASTs filterEqualConstraints(ConstraintType selection) const;
 
     ConstraintsExpressions getExpressionsToCheck(const Context & context, const NamesAndTypesList & source_columns_) const;