void Analyzer::compute_table_stat(const TableID& tab_id) {
TableDescriptor* table = Catalog::getInstance()->getTable(tab_id);
LogicalOperator* scan = new LogicalScan(table->getProjectoin(0));
std::vector<Attribute> group_by_attributes;
std::vector<Attribute> aggregation_attributes;
aggregation_attributes.push_back(Attribute(ATTRIBUTE_ANY));
std::vector<PhysicalAggregation::State::Aggregation> aggregation_function;
aggregation_function.push_back(PhysicalAggregation::State::kCount);
LogicalOperator* agg = new LogicalAggregation(
group_by_attributes, aggregation_attributes, aggregation_function, scan);
LogicalOperator* root =
new LogicalQueryPlanRoot(0, agg, LogicalQueryPlanRoot::kResultCollector);
PhysicalOperatorBase* collector =
root->GetPhysicalPlan(1024 * 64 - sizeof(unsigned));
collector->Open();
collector->Next(0);
collector->Close();
ResultSet* resultset = collector->GetResultSet();
ResultSet::Iterator it = resultset->createIterator();
BlockStreamBase::BlockStreamTraverseIterator* b_it =
it.nextBlock()->createIterator();
const unsigned long tuple_count = *(unsigned long*)b_it->nextTuple();
BlockStreamBase* block;
while (block = it.nextBlock()) {
BlockStreamBase::BlockStreamTraverseIterator* b_it =
block->createIterator();
}
TableStatistic* tab_stat = new TableStatistic();
tab_stat->number_of_tuples_ = tuple_count;
printf("Statistics for table %s is gathered!\n",
Catalog::getInstance()->getTable(tab_id)->getTableName().c_str());
tab_stat->print();
StatManager::getInstance()->setTableStatistic(tab_id, tab_stat);
resultset->destory();
root->~LogicalOperator();
}
unsigned long Analyzer::getDistinctCardinality(const AttributeID& attr_id) {
LogicalOperator* scan = new LogicalScan(
Catalog::getInstance()->getTable(attr_id.table_id)->getProjectoin(0));
std::vector<Attribute> group_by_attributes;
group_by_attributes.push_back(
Catalog::getInstance()->getTable(attr_id.table_id)->getAttribute(
attr_id.offset));
LogicalOperator* agg = new LogicalAggregation(
group_by_attributes, std::vector<Attribute>(),
std::vector<PhysicalAggregation::State::Aggregation>(), scan);
std::vector<Attribute> aggregation_attributes;
aggregation_attributes.push_back(Attribute(ATTRIBUTE_ANY));
std::vector<PhysicalAggregation::State::Aggregation> aggregation_function;
aggregation_function.push_back(PhysicalAggregation::State::kCount);
LogicalOperator* count_agg =
new LogicalAggregation(std::vector<Attribute>(), aggregation_attributes,
aggregation_function, agg);
LogicalOperator* root = new LogicalQueryPlanRoot(
0, count_agg, LogicalQueryPlanRoot::kResultCollector);
PhysicalOperatorBase* collector =
root->GetPhysicalPlan(1024 * 64 - sizeof(unsigned));
collector->Open();
collector->Next(0);
collector->Close();
ResultSet* resultset = collector->GetResultSet();
ResultSet::Iterator it = resultset->createIterator();
BlockStreamBase::BlockStreamTraverseIterator* b_it =
it.nextBlock()->createIterator();
const unsigned long distinct_cardinality = *(unsigned long*)b_it->nextTuple();
resultset->destory();
collector->~PhysicalOperatorBase();
root->~LogicalOperator();
return distinct_cardinality;
}