/**
 * Copyright (c) 2021 OceanBase
 * OceanBase CE is licensed under Mulan PubL v2.
 * You can use this software according to the terms and conditions of the Mulan PubL v2.
 * You may obtain a copy of Mulan PubL v2 at:
 *          http://license.coscl.org.cn/MulanPubL-2.0
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PubL v2 for more details.
 */

#ifndef SRC_SQL_ENGINE_EXPR_OB_EXPR_GET_SUBPROGRAM_VAR_H_
#define SRC_SQL_ENGINE_EXPR_OB_EXPR_GET_SUBPROGRAM_VAR_H_
#include "lib/ob_name_def.h"
#include "sql/engine/expr/ob_expr_operator.h"
#include "sql/session/ob_sql_session_info.h"

namespace oceanbase
{
namespace sql
{
class ObExprGetSubprogramVar : public ObFuncExprOperator
{
public:
  explicit ObExprGetSubprogramVar(common::ObIAllocator &alloc)
    : ObFuncExprOperator(
        alloc, T_OP_GET_SUBPROGRAM_VAR, N_GET_SUBPROGRAM_VAR, PARAM_NUM_UNKNOWN, VALID_FOR_GENERATED_COL, NOT_ROW_DIMENSION, INTERNAL_IN_MYSQL_MODE)
  {}

  virtual ~ObExprGetSubprogramVar() {};

  virtual int calc_result_typeN(ObExprResType &type,
                           ObExprResType *types,
                           int64_t param_num,
                           ObExprTypeCtx &type_ctx) const;
  virtual int cg_expr(ObExprCGCtx &op_cg_ctx,
                      const ObRawExpr &raw_expr,
                      ObExpr &rt_expr) const override;
  static int calc_get_subprogram_var(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &expr_datum);
private:
  // disallow copy
  DISALLOW_COPY_AND_ASSIGN(ObExprGetSubprogramVar);
};
} //end namespace sql
} //end namespace oceanbase
#endif /* SRC_SQL_ENGINE_EXPR_OB_EXPR_GET_SUBPROGRAM_VAR_H_ */