Files
oceanbase/src/sql/optimizer/ob_raw_expr_get_hash_value.h
wangzelin.wzl 93a1074b0c patch 4.0
2022-10-24 17:57:12 +08:00

60 lines
1.9 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 _OB_RAW_EXPR_GET_HASH_VALUE_H
#define _OB_RAW_EXPR_GET_HASH_VALUE_H 1
#include "sql/optimizer/ob_logical_operator.h"
#include "sql/resolver/expr/ob_raw_expr.h"
namespace oceanbase {
namespace sql {
/**
* This class is used to traverse an expression tree in a post-order fashion to
* add all required expressions into the context data structure, which is used
* during output expr allocation.
*/
class ObRawExprGetHashValue: public ObRawExprVisitor
{
public:
ObRawExprGetHashValue(uint64_t seed) : seed_(seed) {}
virtual ~ObRawExprGetHashValue() {}
/**
* The starting point
*/
int get_hash_value(ObRawExpr &expr);
/// interface of ObRawExprVisitor
virtual int visit(ObConstRawExpr &expr);
virtual int visit(ObVarRawExpr &expr);
virtual int visit(ObOpPseudoColumnRawExpr &expr);
virtual int visit(ObQueryRefRawExpr &expr);
virtual int visit(ObColumnRefRawExpr &expr);
virtual int visit(ObOpRawExpr &expr);
virtual int visit(ObCaseOpRawExpr &expr);
virtual int visit(ObAggFunRawExpr &expr);
virtual int visit(ObSysFunRawExpr &expr);
virtual int visit(ObSetOpRawExpr &expr);
virtual int visit(ObPlQueryRefRawExpr &expr);
private:
int add_expr(ObRawExpr &expr);
private:
uint64_t seed_;
// disallow copy
DISALLOW_COPY_AND_ASSIGN(ObRawExprGetHashValue);
};
}
}
#endif // _OB_RAW_EXPR_GET_HASH_VALUE_H