MySQL 5 Installation#

Open a command line with administrator privileges, go to the /bin directory, and enter mysqld.exe --install&&net start mysql

Changing the Password#

For the first change, enter mysqladmin -u root password "new_password". To change an existing password, enter mysqladmin -u root -p password "new_password", then enter the original old password.

IDE Settings#

First, add mysql5\include to the include directory. Add mysql5\lib\opt to the lib directory. (Optional) Add libmysql.lib to the lib files linked by the linker. If you can’t figure out how to add libmysql.lib, you can skip this step

Using C++ Code to Connect to and Operate the Database#

Required Header Files#

First, include the following header files

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#include <winsock2.h>
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#include <mysql.h>
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#pragma comment(lib,"libmysql.lib") //If you've set libmysql.lib in the IDE, you don't need this line, but adding it won't hurt either

Connecting to the Database#

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MYSQL mysqlconn;
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mysql_init(&mysqlconn);
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char * host="127.0.0.1";        //Server address
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int port=3306;                  //Port
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char * username="root";         //Username
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char * password="1234567890";   //Password
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char * dbname="virus";          //Database name
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(mysql_real_connect(&mysqlconn,host,username,password,dbname,port,NULL,CLIENT_FOUND_ROWS) != NULL)?cout<<"success"<<endl:cout<<"fail"<<endl;
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mysql_query(&mysqlconn,"set names gbk");    //After connecting, set the encoding to GBK

Reading Data from the Database#

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void getdata()
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{
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    MYSQL_RES *     mysql_res;
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    MYSQL_FIELD *   mysql_field;
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    MYSQL_ROW       mysql_row;
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    char * sql="select * from virus_data where city_deadCount>50";
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    if(mysql_query(&mysqlconn,sql)==0)
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    {
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        cout<<"get data success"<<endl;
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        mysql_res=mysql_store_result(&mysqlconn);
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        if(mysql_res)
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        {
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            int fiendcount=mysql_num_fields(mysql_res);
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            int rowcount=mysql_num_rows(mysql_res);
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            cout<<fiendcount<<endl;
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            cout<<rowcount<<endl;
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            for(int i=0;i<fiendcount;i++)
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            {
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                mysql_field=mysql_fetch_field(mysql_res);
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                cout<<mysql_field->name<<" ";
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            }
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            cout<<endl;
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            for(int i=0;i<rowcount;i++)
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            {
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                mysql_row=mysql_fetch_row(mysql_res);
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                for(int ja=0;ja<fiendcount;ja++)
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                {
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                    cout<<mysql_row[ja]<<" ";
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                }
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                cout<<endl;
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            }
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        }
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    }else{
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        cout<<"get data fail"<<endl;
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    }
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}

Modifying Data in the Database#

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string sql;
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sqla = "update item set qty=" + tmp + " where itemid='" + itemid + "'";         //Update
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sqlb = "delete from user where userid='" + userid + "'";              //Delete
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sqlc = "insert into datemax(date,value) values('" + date + "','" + "1" + "');";     //Insert
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mysql_query(&mysqlconn, sql);