数据库MySql类库系列(八)-预处理执行Sql方式的示例

2019-11-06 06:11:33

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本文是对之前预处理执行Sql方式的示例程序TestDB

基于前文的DBService，PRepareOperatorSelect，PrepareOperatorUpdate

首先是数据表定义：

还是一个简单的账号表，包括3个字段：帐号名（最长20个字符，主键），账号密码（最长20个字符），账号id（无符号整数，自增字段）

sql如下：

CREATE TABLE `account` (  `account_name` varchar(20) NOT NULL,  `account_key` varchar(20) NOT NULL,  `account_id` int(11) unsigned NOT NULL AUTO_INCREMENT,  PRIMARY KEY (`account_name`),  UNIQUE KEY `account_id_index` (`account_id`)) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
下面演示对这张表，以预处理执行sql的方式，实现增、删、改、查
首先，实现一个PrepareDBService，继承DBService
实现4个接口：
	// 分别实现增、删、改、查bool SelectAccount(const char(&name)[MaxAccountLen], char(&key)[MaxAccountLen], unsigned int& id);bool InsertAccount(const char(&name)[MaxAccountLen], const char(&key)[MaxAccountLen]);bool UpdateAccount(const char(&name)[MaxAccountLen], const char(&key)[MaxAccountLen]);bool DeleteAccount(const char(&name)[MaxAccountLen]);对应4个操作对象（2种：增删改对应PrepareOperatorUpdate，查找对应PrepareOperatorSelect）
// 对应增、删、改、查四种操作的预处理的绑定参数/绑定结果void PrepareSelectAccount();void PrepareInsertAccount();void PrepareUpdateAccount();void PrepareDeleteAccount();	// 对应增、删、改、查四种操作对象common::db::PrepareOperatorSelect m_select_account;common::db::PrepareOperatorUpdate m_insert_account;common::db::PrepareOperatorUpdate m_update_account;common::db::PrepareOperatorUpdate m_delete_account;主函数：
1、插入一个账号，账号名=Test001，密码=0000001的账号
2、更新这个账号的密码，改为1111111
3、查询这个账号名=Test001的账号信息（账号名，密码，id），此时密码应为第2步已经修改后的密码，如果该表此前没有插入过记录，此时id应该为1，每执行一次插入id+1
4、删除这个账号名=Test001的账号
5、再次查询这个账号名=Test001的账号信息，此时应该没有对应的数据
执行结果截图：
DBService的子类实现：
PrepareDBService.h：
#ifndef __PrepareDBService_H__#define	__PrepareDBService_H__#include "DBService.h"#include "PrepareOperatorSelect.h"#include "PrepareOperatorUpdate.h"class PrepareDBService : public common::db::DBService{public:	PrepareDBService();	virtual ~PrepareDBService();public:	// 最大账号，密码字符串长度为20个字符	static const unsigned int MaxAccountLen = 20;public:	virtual bool ProcessStart();	virtual void ProcessStop();	// 分别实现增、删、改、查	bool SelectAccount(const char(&name)[MaxAccountLen], char(&key)[MaxAccountLen], unsigned int& id);	bool InsertAccount(const char(&name)[MaxAccountLen], const char(&key)[MaxAccountLen]);	bool UpdateAccount(const char(&name)[MaxAccountLen], const char(&key)[MaxAccountLen]);	bool DeleteAccount(const char(&name)[MaxAccountLen]);private:	// 账号属性类型	enum AccountPropertyType	{		account_name = 0,		// 帐号名称		account_key,			// 账号密码		account_id,				// 账号id		account_property_count,	};	unsigned long m_property_len[account_property_count];	void InitPropertyLen();	// 账号信息绑定值	char m_account_name[MaxAccountLen];	char m_account_key[MaxAccountLen];	unsigned int m_account_id;	// 各个预处理的绑定参数/绑定结果	void PrepareSelectAccount();	void PrepareInsertAccount();	void PrepareUpdateAccount();	void PrepareDeleteAccount();	// 对应增、删、改、查四种操作对象	common::db::PrepareOperatorSelect m_select_account;	common::db::PrepareOperatorUpdate m_insert_account;	common::db::PrepareOperatorUpdate m_update_account;	common::db::PrepareOperatorUpdate m_delete_account;};#endif
PrepareDBService.cpp：
#include "PrepareDBService.h"PrepareDBService::PrepareDBService(){}PrepareDBService::~PrepareDBService(){}bool PrepareDBService::ProcessStart(){	//预处理sql	InitPropertyLen();	PrepareSelectAccount();	PrepareInsertAccount();	PrepareUpdateAccount();	PrepareDeleteAccount();	return true;}void PrepareDBService::ProcessStop(){	m_select_account.Release();	m_insert_account.Release();	m_update_account.Release();	m_delete_account.Release();}void PrepareDBService::InitPropertyLen(){	m_property_len[account_name] = sizeof(m_account_name);	m_property_len[account_key] = sizeof(m_account_key);	m_property_len[account_id] = sizeof(m_account_id);}void PrepareDBService::PrepareSelectAccount(){	//预处理sql	m_select_account.BindSql(m_Connect,		"select * from account where account_name = ?;");	m_select_account.BindResult("%s,%s,%u",		m_account_name, &m_property_len[account_name],		m_account_key, &m_property_len[account_key],		&m_account_id);	m_select_account.BindParameter("%s",		m_account_name, &m_property_len[account_name]);}bool PrepareDBService::SelectAccount(const char(&name)[MaxAccountLen], char(&key)[MaxAccountLen], unsigned int& id){	boost::mutex::scoped_lock lock(m_Lock);	strcpy(m_account_name, name);	if (m_select_account.DoOperator())	{		if (m_select_account.FetchResult())		{			strcpy(key, m_account_key);			id = m_account_id;			m_select_account.FreeResult();			return true;		}		else		{			return false;		}	}	else	{		return false;	}}void PrepareDBService::PrepareInsertAccount(){	m_insert_account.BindSql(m_Connect,		"insert into account(account_name, account_key) values(?, ?);");	m_insert_account.BindParameter("%s,%s",		m_account_name, &m_property_len[account_name],		m_account_key, &m_property_len[account_key]);}bool PrepareDBService::InsertAccount(const char(&name)[MaxAccountLen], const char(&key)[MaxAccountLen]){	boost::mutex::scoped_lock lock(m_Lock);	strcpy(m_account_name, name);	strcpy(m_account_key, key);	return m_insert_account.DoOperator();}void PrepareDBService::PrepareUpdateAccount(){	m_update_account.BindSql(m_Connect,		"update account set account_key = ? where account_name = ?;");	m_update_account.BindParameter("%s,%s",		m_account_key, &m_property_len[account_key],		m_account_name, &m_property_len[account_name]);}bool PrepareDBService::UpdateAccount(const char(&name)[MaxAccountLen], const char(&key)[MaxAccountLen]){	boost::mutex::scoped_lock lock(m_Lock);	strcpy(m_account_name, name);	strcpy(m_account_key, key);	return m_update_account.DoOperator();}void PrepareDBService::PrepareDeleteAccount(){	m_delete_account.BindSql(m_Connect,		"delete from account where account_name = ?;");	m_delete_account.BindParameter("%s",		m_account_name, &m_property_len[account_name]);}bool PrepareDBService::DeleteAccount(const char(&name)[MaxAccountLen]){	boost::mutex::scoped_lock lock(m_Lock);	strcpy(m_account_name, name);	return m_delete_account.DoOperator();}
主函数TestDB.cpp：
#include <iostream>#include "PrepareDBService.h"void PrepareAccount(){	char accountName[PrepareDBService::MaxAccountLen] = { 0 };	char accountKey[PrepareDBService::MaxAccountLen] = { 0 };	unsigned int accountId = 0;	PrepareDBService service;	service.Start("127.0.0.1", 3306, "root", "root", "account");	/////////////////////////Insert/////////////////////////	memset(accountName, 0x00, sizeof(accountName));	strcpy(accountName, "Test001");	memset(accountKey, 0x00, sizeof(accountKey));	strcpy(accountKey, "0000001");	if (service.InsertAccount(accountName, accountKey))	{		std::cout << "InsertAccount name = " << accountName << ", key = " << accountKey << " success" << std::endl;	}	/////////////////////////Update/////////////////////////	memset(accountName, 0x00, sizeof(accountName));	strcpy(accountName, "Test001");	memset(accountKey, 0x00, sizeof(accountKey));	strcpy(accountKey, "1111111");	if (service.UpdateAccount(accountName, accountKey))	{		std::cout << "UpdateAccount name = " << accountName << ", key = " << accountKey << " success" << std::endl;	}	/////////////////////////Select/////////////////////////	memset(accountName, 0x00, sizeof(accountName));	strcpy(accountName, "Test001");	if (service.SelectAccount(accountName, accountKey, accountId))	{		std::cout << "SelectAccount name = " << accountName << ", key = " << accountKey << " , id = " << accountId << std::endl;	}	else	{		std::cout << "no result" << std::endl;	}	/////////////////////////Delete/////////////////////////	memset(accountName, 0x00, sizeof(accountName));	strcpy(accountName, "Test001");	if (service.DeleteAccount(accountName))	{		std::cout << "DeleteAccount name = " << accountName << " success" << std::endl;	}	/////////////////////////Select/////////////////////////	memset(accountName, 0x00, sizeof(accountName));	strcpy(accountName, "Test001");	if (service.SelectAccount(accountName, accountKey, accountId))	{		std::cout << "SelectAccount name = " << accountName << ", key = " << accountKey << " , id = " << accountId << std::endl;	}	else	{		std::cout << "no result" << std::endl;	}	service.Stop();}int main(int argc, char* argv[]){	PrepareAccount();	system("pause");	return 0;}