错误：'sql'没有命名类型sql：：Connection connect_mysql（）;有没有方法可以从这个函数返回连接对象？我知道在C中返回连接对象，但在C++中没有。
编辑版本：connect_mysql（）的返回类型已更改为sql：：Connection *。以前它是sql：：Connection。

#include <iostream>
#include <fstream>
#include <stdlib.h>
#include <string.h>
#include<mysql/mysql.h>
#include<cppconn/driver.h>
#include<cppconn/exception.h>
#include<cppconn/resultset.h>
#include<cppconn/statement.h>
sql::Connection * connect_mysql();    

       int main()
       {
            sql::Connection *con;
            con = connect_mysql();
            return 0;
       }


      sql::Connection * connect_mysql()
        {
            cout << "CONNECTING DATABASE..............."<<endl;
            try{
                    cout<<"inside try while connecting to mysql"<<endl;
                    sql::Driver *driver;
                    sql::Connection *con;
                    sql::Statement *stmt;
                    sql::ResultSet *res;
                    driver = get_driver_instance();
                    con = driver->connect("localhost","root","Aricent@123");
                   con->setSchema( "COE" );                            
                    stmt = con->createStatement();                           
                    res = stmt->executeQuery( "show tables" );
                    while( res->next() )
                    {
                            cout<<"MYSQL replies:"<<endl;
                            cout<<res->getInt(1);
                            cout<<res->getString(1)<<endl;
                    }
           } 
        catch( exception e )
            {

                    cout << "# ERR: SQLException in " << __FILE__;                   
                    cout << "# ERR: ";
                    cout << " (MySQL error code: ";
                    cout << ", SQLState: ";
            }
            return con;
        }