query_result.h

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#pragma once
 
#include <string>
 
#include "api.h"
#include "arrow.h"
#include "types.h"
#include "kuzu_fwd.h"
#include "flat_tuple.h"
#include "query_summary.h"
 
namespace kuzu {
namespace main {
 
class QueryResult {
 friend class Connection;
 friend class ClientContext;
 class QueryResultIterator {
 private:
 QueryResult* currentResult;
 
 public:
 QueryResultIterator() = default;
 
 explicit QueryResultIterator(QueryResult* startResult) : currentResult(startResult) {}
 
 void operator++() {
 if (currentResult) {
 currentResult = currentResult->nextQueryResult.get();
 }
 }
 
 bool isEnd() const { return currentResult == nullptr; }
 
 bool hasNextQueryResult() const { return currentResult->nextQueryResult != nullptr; }
 
 QueryResult* getCurrentResult() const { return currentResult; }
 };
 
public:
 KUZU_API QueryResult();
 
 explicit QueryResult(const PreparedSummary& preparedSummary);
 KUZU_API ~QueryResult();
 KUZU_API bool isSuccess() const;
 KUZU_API std::string getErrorMessage() const;
 KUZU_API size_t getNumColumns() const;
 KUZU_API std::vector<std::string> getColumnNames() const;
 KUZU_API std::vector<common::LogicalType> getColumnDataTypes() const;
 KUZU_API uint64_t getNumTuples() const;
 KUZU_API QuerySummary* getQuerySummary() const;
 KUZU_API bool hasNext() const;
 KUZU_API bool hasNextQueryResult() const;
 KUZU_API QueryResult* getNextQueryResult();
 
 std::unique_ptr<QueryResult> nextQueryResult;
 KUZU_API std::shared_ptr<processor::FlatTuple> getNext();
 KUZU_API std::string toString();
 
 KUZU_API void resetIterator();
 
 processor::FactorizedTable* getTable() { return factorizedTable.get(); }
 
 KUZU_API std::unique_ptr<ArrowSchema> getArrowSchema() const;
 
 KUZU_API std::unique_ptr<ArrowArray> getNextArrowChunk(int64_t chunkSize);
 
private:
 void initResultTableAndIterator(std::shared_ptr<processor::FactorizedTable> factorizedTable_,
 const std::vector<std::shared_ptr<binder::Expression>>& columns);
 void validateQuerySucceed() const;
 
private:
 // execution status
 bool success = true;
 std::string errMsg;
 
 // header information
 std::vector<std::string> columnNames;
 std::vector<common::LogicalType> columnDataTypes;
 // data
 std::shared_ptr<processor::FactorizedTable> factorizedTable;
 std::unique_ptr<processor::FlatTupleIterator> iterator;
 std::shared_ptr<processor::FlatTuple> tuple;
 
 // execution statistics
 std::unique_ptr<QuerySummary> querySummary;
 
 // query iterator
 QueryResultIterator queryResultIterator;
};
 
} // namespace main
} // namespace kuzu