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Delete unnecessary scanall index variables

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This commit is contained in:
Josip Mrden
2023-06-20 14:14:10 +02:00
parent 24ade79579
commit e0e0b19e44
1 changed files with 23 additions and 25 deletions
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48
src/query/plan/rewrite/index_lookup.hpp
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@@ -47,7 +47,6 @@ struct SymbolStatistics {
};
struct Scope {
bool in_optional{false};
std::unordered_map<std::string, SymbolStatistics> symbol_stats;
};
@@ -114,12 +113,13 @@ class IndexLookupRewriter final : public HierarchicalLogicalOperatorVisitor {
return true;
}
ScanAll dst_scan(expand.input(), expand.common_.node_symbol, expand.view_);
auto indexed_scan = GenScanByIndex(dst_scan, FLAGS_query_vertex_count_to_expand_existing);
if (indexed_scan) {
if (utils::Contains(scope_.symbol_stats, expand.common_.node_symbol.name()) &&
utils::Contains(scope_.symbol_stats, expand.input_symbol_.name())) {
auto src_cost = scope_.symbol_stats[expand.input_symbol_.name()].degree;
auto dest_cost = scope_.symbol_stats[expand.common_.node_symbol.name()].cardinality;
// if both are matched upfront, see by index statistics how to expand
if (HasStatsFor(expand.common_.node_symbol) && HasStatsFor(expand.input_symbol_)) {
auto src_cost = GetStatsFor(expand.input_symbol_).value().degree;
auto dest_cost = GetStatsFor(expand.common_.node_symbol).value().cardinality;
if (dest_cost < src_cost) {
expand.set_input(std::move(indexed_scan));
@@ -182,7 +182,6 @@ class IndexLookupRewriter final : public HierarchicalLogicalOperatorVisitor {
}
bool PreVisit(Optional &op) override {
scope_.in_optional = true;
prev_ops_.push_back(&op);
op.input()->Accept(*this);
RewriteBranch(&op.optional_);
@@ -190,7 +189,6 @@ class IndexLookupRewriter final : public HierarchicalLogicalOperatorVisitor {
}
bool PostVisit(Optional &) override {
scope_.in_optional = false;
prev_ops_.pop_back();
return true;
}
@@ -708,6 +706,14 @@ class IndexLookupRewriter final : public HierarchicalLogicalOperatorVisitor {
std::vector<Expression *> removed_expressions;
filters_.EraseLabelFilter(node_symbol, found_index->label, &removed_expressions);
filter_exprs_for_removal_.insert(removed_expressions.begin(), removed_expressions.end());
auto index_stats = db_->GetIndexStats(GetLabel(found_index->label), GetProperty(prop_filter.property_));
if (index_stats.has_value()) {
scope_.symbol_stats[node_symbol.name()] = SymbolStatistics{.name = node_symbol.name(),
.cardinality = index_stats.value().count,
.degree = index_stats.value().avg_degree};
}
if (prop_filter.lower_bound_ || prop_filter.upper_bound_) {
return std::make_unique<ScanAllByLabelPropertyRange>(
input, node_symbol, GetLabel(found_index->label), GetProperty(prop_filter.property_),
@@ -726,38 +732,21 @@ class IndexLookupRewriter final : public HierarchicalLogicalOperatorVisitor {
auto *expression = ast_storage_->Create<Identifier>(symbol.name_);
expression->MapTo(symbol);
auto unwind_operator = std::make_unique<Unwind>(input, prop_filter.value_, symbol);
auto index_stats = db_->GetIndexStats(GetLabel(found_index->label), GetProperty(prop_filter.property_));
if (index_stats.has_value()) {
scope_.symbol_stats[node_symbol.name()] = SymbolStatistics{.name = node_symbol.name(),
.cardinality = index_stats.value().count,
.degree = index_stats.value().avg_degree};
}
return std::make_unique<ScanAllByLabelPropertyValue>(
std::move(unwind_operator), node_symbol, GetLabel(found_index->label), GetProperty(prop_filter.property_),
prop_filter.property_.name, expression, view);
} else if (prop_filter.type_ == PropertyFilter::Type::IS_NOT_NULL) {
auto index_stats = db_->GetIndexStats(GetLabel(found_index->label), GetProperty(prop_filter.property_));
if (index_stats.has_value()) {
scope_.symbol_stats[node_symbol.name()] = SymbolStatistics{.name = node_symbol.name(),
.cardinality = index_stats.value().count,
.degree = index_stats.value().avg_degree};
}
return std::make_unique<ScanAllByLabelProperty>(input, node_symbol, GetLabel(found_index->label),
GetProperty(prop_filter.property_), prop_filter.property_.name,
view);
} else {
MG_ASSERT(prop_filter.value_, "Property filter should either have bounds or a value expression.");
auto index_stats = db_->GetIndexStats(GetLabel(found_index->label), GetProperty(prop_filter.property_));
if (index_stats.has_value()) {
scope_.symbol_stats[node_symbol.name()] = SymbolStatistics{.name = node_symbol.name(),
.cardinality = index_stats.value().count,
.degree = index_stats.value().avg_degree};
}
return std::make_unique<ScanAllByLabelPropertyValue>(input, node_symbol, GetLabel(found_index->label),
GetProperty(prop_filter.property_),
prop_filter.property_.name, prop_filter.value_, view);
}
}
auto maybe_label = FindBestLabelIndex(labels);
if (!maybe_label) return nullptr;
const auto &label = *maybe_label;
@@ -766,6 +755,7 @@ class IndexLookupRewriter final : public HierarchicalLogicalOperatorVisitor {
// than the allowed count.
return nullptr;
}
std::vector<Expression *> removed_expressions;
filters_.EraseLabelFilter(node_symbol, label, &removed_expressions);
filter_exprs_for_removal_.insert(removed_expressions.begin(), removed_expressions.end());
@@ -777,6 +767,14 @@ class IndexLookupRewriter final : public HierarchicalLogicalOperatorVisitor {
}
return std::make_unique<ScanAllByLabel>(input, node_symbol, GetLabel(label), view);
}
bool HasStatsFor(Symbol &symbol) { return utils::Contains(scope_.symbol_stats, symbol.name()); }
std::optional<SymbolStatistics> GetStatsFor(Symbol &symbol) {
if (!HasStatsFor(symbol)) {
return std::nullopt;
}
return scope_.symbol_stats[symbol.name()];
}
};
} // namespace impl