C++操作MySQL的实现示例

#include <iostream>
#include<iomanip>
#include "winsock.h" 
#include "mysql.h" 
#pragma comment(lib,"libmySQL.lib")

using namespace std;

int main()
{
 MYSQL* m_sqlCon;
 MYSQL_RES* res_set;
 MYSQL_ROW row;
 MYSQL_FIELD* field;

 m_sqlCon = mysql_init((MYSQL*)0);
 if (!mysql_real_connect(m_sqlCon, "localhost", "root", "123456", "test", 3306, NULL, 0))
 {
  cerr << "Failed to connect to database: Error: " << mysql_error(m_sqlCon) << endl;
 }
 else
 {
  cerr << "Successfully connected to Database." << endl;
  cout << endl;

  string pQuery = "select * from my_table";
  int status = mysql_real_query(m_sqlCon, pQuery.c_str(), (UINT)strlen(pQuery.c_str()));  //输入命令

  res_set = mysql_store_result(m_sqlCon);

  field = mysql_fetch_fields(res_set); //获取所有列名
  int field_count = mysql_field_count(m_sqlCon);  //获取列数

             
  for (int i = 0; i < field_count; i++) //输出所有列名
  {
   cout << setw(15) << field[i].name; //总共占15格
  }
  cout << endl;

  int row_count = mysql_num_rows(res_set); //获取行数

  while (row = mysql_fetch_row(res_set))  //输出所有行数据
  {
   for (int i = 0; i < field_count; i++)
   {
    cout << setw(15) << row[i];
   }
   cout << endl;
  }
 }

 mysql_close(m_sqlCon);

 system("pause");
 return 0;
}

#include <iostream>
#include <map>
#include <string>
#include <memory>
#include "mysql_driver.h"
#include "mysql_connection.h"
#include "cppconn/driver.h"
#include "cppconn/statement.h"
#include "cppconn/prepared_statement.h"
#include "cppconn/metadata.h"
#include "cppconn/exception.h"
 
using namespace std;
using namespace sql;
 
int main()
{
  sql::mysql::MySQL_Driver *driver = 0;
  sql::Connection *conn = 0;
 
  try
  {
    driver = sql::mysql::get_mysql_driver_instance();
    conn = driver->connect("tcp://localhost:3306/booktik", "root", "123456");
    cout << "连接成功" << endl;
  }
  catch (...)
  {
    cout << "连接失败" << endl;
  }
  sql::Statement* stat = conn->createStatement();
  stat->execute("set names 'gbk'");
  ResultSet *res;
  res = stat->executeQuery("SELECT * FROM BOOK");
  while (res->next())
  {
    cout << "BOOKNAME:" << res->getString("bookname") << endl;
    cout << "  SIZE:" << res->getString("size") << endl;
  }
  if (conn != 0)
  {
    delete conn;
  }
}

#include <iostream>
#include <string>
#include "/usr/include/mysql/mysql.h"

using namespace std;

class MyDb 
{
public:
 MyDb();
 ~MyDb();
 bool initDB(string host, string user,string pwd,string db_name, int port);
 bool exeSQL(string sql);

private:
 MYSQL *mysql;
 MYSQL_RES *result;
 MYSQL_ROW row;
};

MyDb::MyDb()
{
 mysql = mysql_init(NULL);

 if(!mysql) {
  cout<<"Error:"<<mysql_error(mysql);
  exit(1);
 }
}

MyDb::~MyDb()
{
 if(mysql) {
  mysql_close(mysql);
 }
}

bool MyDb::initDB(string host, string user, string passwd, string db_name, int port = 3306)
{
 mysql = mysql_real_connect(mysql, host.c_str(),
    user.c_str(), passwd.c_str(), db_name.c_str(), port, NULL, 0);
 if(!mysql) {
  cout << "Error: " << mysql_error(mysql);
  exit(1);
 }

 return true;
}

bool MyDb::exeSQL(string sql)
{
 //mysql_query()执行成功返回0,执行失败返回非0值。
 if (mysql_query(mysql,sql.c_str())) {
  cout<<"Query Error: "<<mysql_error(mysql);
  return false;
 }

 result = mysql_store_result(mysql);

 if (result) {
  //获取结果集中总共的字段数，即列数
  int num_fields = mysql_num_fields(result);
  unsigned long long num_rows = mysql_num_rows(result);

  for(unsigned long long i = 0; i < num_rows; i++) {
   row = mysql_fetch_row(result);
   if(!row) {
    break;
   }

   for(int j=0;j<num_fields;j++) {
    cout<<row[j]<<"\t\t";
   }
   cout<<endl;
  }
 } else {
  //代表执行的是update,insert,delete类的非查询语句
  if (mysql_field_count(mysql) == 0) {
   // 返回update,insert,delete影响的行数
   unsigned long long num_rows = mysql_affected_rows(mysql);

   return num_rows;
  } else {
   cout << "Get result error: " << mysql_error(mysql);
   return false;
  }
 }

 return true;
}

int main() 
{
 MyDb db;

 string host = "127.0.0.1";
 string user = "skynet";
 string passwd = "123456";
 string dbName = "skynet";
 int port = 3306;

 //连接数据库
 bool conn = db.initDB(host, user, passwd, dbName, port);

 if (!conn) {
  cout<<"connect fails\n";
 }

 cout<<"ok" <<endl;

 //将所有用户信息读出，并输出。
 string sql = "SELECT * from test;";
 db.exeSQL(sql);

 return 0;
}