Files
oceanbase/src/sql/engine/expr/ob_expr_wrapper_inner.h
2023-03-17 20:57:21 +08:00

60 lines
1.8 KiB
C++

/**
* 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 OCEANBASE_EXPR_OB_EXPR_WRAPPER_INNER_H_
#define OCEANBASE_EXPR_OB_EXPR_WRAPPER_INNER_H_
#include "sql/engine/expr/ob_expr_operator.h"
namespace oceanbase
{
namespace sql
{
//
// remove_const() is added above const expr to resolve the const value overwrite problem
// in static typing engine. e.g.:
//
// update t1 set (c1, c2) = (select 1, 2 from t2);
//
// will be rewrite to:
// update t1 set (c1, c2) = (select remove_const(1), remove_const(2) from t2);
//
//
// remove_const(1), remove_const(2) will be overwrite when subquery is empty
// instead of const value: 1, 2
//
// see:
//
class ObExprWrapperInner : public ObFuncExprOperator
{
public:
explicit ObExprWrapperInner(common::ObIAllocator &alloc);
virtual ~ObExprWrapperInner() {}
virtual int calc_result_type1(ObExprResType &type,
ObExprResType &arg,
common::ObExprTypeCtx &type_ctx) const override;
virtual int cg_expr(ObExprCGCtx &op_cg_ctx,
const ObRawExpr &raw_expr,
ObExpr &rt_expr) const override;
static int eval_wrapper_inner(const ObExpr &expr, ObEvalCtx &ctx, ObDatum &expr_datum);
private:
DISALLOW_COPY_AND_ASSIGN(ObExprWrapperInner);
};
} // namespace sql
} // namespace oceanbase
#endif // OCEANBASE_EXPR_OB_EXPR_WRAPPER_INNER_H_