be/src/service/hs2-util.h

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#include "gen-cpp/ImpalaHiveServer2Service.h"
#include "gen-cpp/Frontend_types.h"

namespace impala {

class RowBatch;
class ScalarExprEvaluator;

/// Utility methods for converting from Impala (either an Expr result or a TColumnValue)
/// to Hive types (either a thrift::TColumnValue (V1->V5) or a TColumn (V6->).

/// For V6->
void TColumnValueToHS2TColumn(const TColumnValue& col_val, const TColumnType& type,
    uint32_t row_idx, apache::hive::service::cli::thrift::TColumn* column);

/// Evaluate 'expr_eval' over the row [start_idx, start_idx + num_rows) from 'batch' into
/// 'column' with 'type' starting at output_row_idx. The caller is responsible for
/// calling RuntimeState::GetQueryStatus() to check for expression evaluation errors.
/// For V6->
void ExprValuesToHS2TColumn(ScalarExprEvaluator* expr_eval, const TColumnType& type,
    RowBatch* batch, int start_idx, int num_rows, uint32_t output_row_idx,
    apache::hive::service::cli::thrift::TColumn* column);

/// For V1->V5
void TColumnValueToHS2TColumnValue(const TColumnValue& col_val, const TColumnType& type,
    apache::hive::service::cli::thrift::TColumnValue* hs2_col_val);

/// For V1->V5
void ExprValueToHS2TColumnValue(const void* value, const TColumnType& type,
    apache::hive::service::cli::thrift::TColumnValue* hs2_col_val);

/// Combine two null columns by appending 'from' to 'to', starting at 'num_rows_before' in
/// 'from', 'start_idx' in 'to', and proceeding for 'num_rows_added' rows.
void StitchNulls(uint32_t num_rows_before, uint32_t num_rows_added, uint32_t start_idx,
    const std::string& from, std::string* to);

void PrintTColumnValue(const apache::hive::service::cli::thrift::TColumnValue& colval,
    std::stringstream* out);

}