数据库MySql类库系列(八)-预处理执行Sql方式的示例

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;

主要的类关系图如下：

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idaccount_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sqlInitPropertyLen();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sqlm_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;}