logical_operator.h

/* Copyright (c) 2021 OceanBase and/or its affiliates. All rights reserved.
miniob is licensed under Mulan PSL v2.
You can use this software according to the terms and conditions of the Mulan PSL v2.
You may obtain a copy of Mulan PSL v2 at:
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See the Mulan PSL v2 for more details. */
 
//
// Created by Wangyunlai on 2022/12/07.
//
 
#pragma once
 
#include <memory>
#include <vector>
 
#include "sql/expr/expression.h"
 
enum class LogicalOperatorType 
{
  CALC,
  TABLE_GET,  
  PREDICATE,  
  PROJECTION, 
  JOIN,       
  INSERT,     
  DELETE,     
  EXPLAIN,    
};
 
class LogicalOperator 
{
public:
  LogicalOperator() = default;
  virtual ~LogicalOperator();
 
  virtual LogicalOperatorType type() const = 0;
 
  void add_child(std::unique_ptr<LogicalOperator> oper);
  std::vector<std::unique_ptr<LogicalOperator>> &children()
  {
    return children_;
  }
  std::vector<std::unique_ptr<Expression>> &expressions()
  {
    return expressions_;
  }
 
protected:
  std::vector<std::unique_ptr<LogicalOperator>> children_;  
 
  std::vector<std::unique_ptr<Expression>> expressions_;    
};