global.h

#pragma once
#include<unordered_map>
#include<cstdio>
#include<iostream>
#include<string>
#include<vector>
#include<cstdlib>
#include<string.h>
#include <map>
#include <iostream>
#include <vector>
#include <string>
#include <map>
#include <random>
#include <chrono>

using namespace std;

// config浜嬪姟绯荤粺鐨勫彉閲忛厤缃?
extern chrono::duration<int64_t> log_timeout;

static constexpr int32_t INVALID_TXN_ID = -1;                   // 鏃犳晥浜嬪姟id
using txn_id_t = int32_t;					// transaction id type

static constexpr int32_t INVALID_LSN = -1;			// 鏃犳晥鏃ュ織璁板綍搴忓彿
using lsn_t = int32_t;						// log sequence number type

// -------------------

const int MAX_NAME_LENGTH = 20;    //鍚勭鍚嶅瓧濡傛暟鎹〃鍚嶃�佸瓧娈靛悕绛夋渶澶ч暱搴?
const int BUFFER_NUM = 200;

enum SQL_type {
	SELECT,
	UPDATE,
	DELETE,
	INSERT
};

enum Distribution_Type {
	//姝ｆ�佸垎甯?
	NORMAL
	//鍧囧寑鍒嗗竷
	,EVENLY
};
struct Distribution;
struct DISTRIBUTION_TYPE {
	//涓�鍏冩潯浠?
	virtual double rate(int op, double value) = 0;
	//浜屽厓鏉′欢
	virtual double binary_rate(int op, const Distribution& dis) = 0;
	virtual void display() = 0;
};
struct NORMAL_dis : public DISTRIBUTION_TYPE {
	double mu;
	double sigma;
	double rate(int op, double value) {
		return 0.5;
	}
	double binary_rate(int op, const Distribution& dis) {
		return 0.5;
	}
	void display() {
		cout << "分布为：高斯分布" << endl;
		cout << "参数：  mu:" << mu << "  sigma:" << sigma << endl;
	}
};
struct EVENLY_dis : public DISTRIBUTION_TYPE {
	double MIN;
	double MAX;
	double rate(int op, double value);
	double binary_rate(int op, const Distribution& dis) {
		return 0.5;
	}
	void display() {
		cout << "分布为：均匀分布" << endl;
		cout << "参数：  max:" << MAX << "  min:" << MIN << endl;
	}
};
struct Distribution {
	Distribution_Type type;
	NORMAL_dis normal_dis;
	EVENLY_dis evenly_dis;
	DISTRIBUTION_TYPE* dis() {
		if (type == NORMAL) return &normal_dis;
		return &evenly_dis;
	}
	
};


class Global_Paras {  //鐢ㄤ簬瀛樻斁涓�浜涘叏灞�鍙橀噺锛屽褰撳墠鏁版嵁搴撱�佺敤鎴风瓑锛屼笉鍙疄渚嬪寲
private:
	Global_Paras();

public:
	static string Current_DB;
	static string Current_User;

	static int Block_Size;	
};



struct RID {
	int blockID;
	int slotID;
	bool operator<(const RID& rhs) const
	{
		if (blockID < rhs.blockID) return true;
		else if (blockID == rhs.blockID && slotID < rhs.slotID) return true;
		return false;
	}
};

// 浜嬪姟绯荤粺瑕佺敤鐨凴ID鍜岃〃鍚嶅瓧鑱斿悎鐨勬爣璇?

struct Trid {
	string relname;
	RID rid;
	// 鍙瀯鎴愪竴鏉¤褰曠殑鍞竴鏍囪瘑
	Trid(string name = "", RID r = RID{}) : relname(name), rid(r) {}
	bool operator < (const Trid& rhs) const {
		return relname < rhs.relname ||
			(relname == rhs.relname && rid < rhs.rid);
	}
};




enum AttrType {
	INT,FLOAT,STRING
};
enum Authority {
	Authority_SELECT, Authority_INSERT, Authority_DELETE, Authority_UPDATE
};
enum IndexType {
	CLUSTER_INDEX,NORMAL_INDEX
};


struct DB_Info {
	char DBName[MAX_NAME_LENGTH];
	char Creator[MAX_NAME_LENGTH];
};
struct User_Info {
	char UserName[MAX_NAME_LENGTH];
	char PassWord[MAX_NAME_LENGTH];
};
struct Rel_Info {
	char Rel_Name[MAX_NAME_LENGTH];
	char Creator[MAX_NAME_LENGTH];
	char DBName[MAX_NAME_LENGTH];
	int Record_Num;
	int PageID_Head;
};
struct Authority_Info {
	char UserName[MAX_NAME_LENGTH];
	char Rel_Name[MAX_NAME_LENGTH];
	char Creator[MAX_NAME_LENGTH];
	char DBName[MAX_NAME_LENGTH];
	bool authority[4];      //authority[SELECT]=true/false
};
struct Page_Info {
	char Rel_Name[MAX_NAME_LENGTH];
	char Creator[MAX_NAME_LENGTH];
	char DBName[MAX_NAME_LENGTH];
	int PageID;
	int NextID;
};
struct Attr_Info {
	char Rel_Name[MAX_NAME_LENGTH];
	char Creator[MAX_NAME_LENGTH];
	char DBName[MAX_NAME_LENGTH];
	char Attr_Name[MAX_NAME_LENGTH];
	AttrType type;
	int Length;
	int Offset;
	Distribution distribution;
	int Num_of_Change_Records;
};
struct Index_Info {
	char Rel_Name[MAX_NAME_LENGTH];
	char Creator[MAX_NAME_LENGTH];
	char DBName[MAX_NAME_LENGTH];
	char Attr_Name[MAX_NAME_LENGTH];
	char Index_Creator[MAX_NAME_LENGTH];
	int Head_PageID;
	IndexType type;
};