Linux mysql c API封装

来源：互联网发布：软件运维工程师知乎编辑：程序博客网时间：2024/06/05 08:53

mysql 是目前使用量最大的关系型数据库，在互联网公司应用非常广泛，在一些非高并发场景下应用MySQL能大幅降低开发运维和部署的成本。

下面是自己封装的c++ 风格的MySQL客户端，相对原生的c api 使用相对更加简便一些

/******************************************************function: mysql c api wrapp for c++ style.author: liuyidate: 2016.04.13version: 1.0******************************************************/#ifndef MYSQL_CONNECTOR#define MYSQL_CONNECTOR#include <stdio.h>#include <iostream>#include <string>#include <vector>#include <mysql/mysql.h>using namespace std;class mysql_connector{public:mysql_connector(){}~mysql_connector(){mysql_close(&m_mysql);}bool init(const string& host, const string& user, const string& pw,   const string& db, int port=3306, const string& code="utf8"){m_host = host;m_user = user;m_pw = pw;m_db = db;m_port = port;m_code = code;return NULL != mysql_init(&m_mysql) && connect() && execute_sql(("set names " + m_code).c_str());}bool reconnect(){close_connect();return connect() && execute_sql(("set names " + m_code).c_str());}void close_connect(){mysql_close(&m_mysql);}bool execute_sql(const string& sql){return 0 == mysql_real_query(&m_mysql, sql.c_str(), sql.size());}bool select_data(const string& sql, vector<vector<string> >& result_matrix){if(!execute_sql(sql))return false;MYSQL_RES *res = mysql_store_result(&m_mysql);if(NULL == res){ mysql_free_result(res);return false;}int numcols = mysql_num_fields(res);MYSQL_ROW row;while(row =  mysql_fetch_row(res)){vector<string> row_vec;row_vec.reserve(numcols);for(int i = 0; i < numcols; i++){row_vec.push_back(row[i]);}result_matrix.push_back(row_vec);}mysql_free_result(res);return true;}string get_error_msg(){char buf[2048] = {0};snprintf(buf, 2047, "error_code=%d, error_msg=%s", mysql_errno(&m_mysql), mysql_error(&m_mysql)); return buf;}private:bool connect(){return NULL != mysql_real_connect(&m_mysql, m_host.c_str(), m_user.c_str(), m_pw.c_str(), m_db.c_str(), m_port, NULL, 0);}private: MYSQL m_mysql; string m_host; string m_user; string m_pw; string m_db; string m_code; int m_port;};#endif

#include "mysql_connector.h"int main(int argc, char* argv[]){mysql_connector conn;cout<<conn.init("127.0.0.1", "newborn", "newbornmysqladmin", "bbloves", 3306, "utf8")<<endl;cout<<conn.reconnect()<<endl;cout<<conn.get_error_msg()<<endl;vector<vector<string> > v;cout<<conn.select_data("select cellphone, mother_name, report_id from report where msg_notify_count < 2", v)<<endl;for(size_t i = 0 ; i < v.size(); i++){for(size_t j = 0; j < v[i].size(); j++)cout<<v[i][j]<<endl;cout<<"---------------"<<endl;}cout<<conn.get_error_msg()<<endl;return 0;}

g++ test_mysql.cpp -L/usr/lib64/mysql -lmysqlclient -lpthread

0 0