stevesearle.com - Techie Stuff

This page documents how to use a MySQL Database from a C++ program. I found it took a bit of working out to get the compile options correct, and created this program to check I had it all working correctly.

If you have problems compiling or linking, please check my FAQ page before contacting me.

To compile this program, the following command is required:

g++ mysql_example.cpp -o mysql_example -Wall -I/usr/include/mysql -L/usr/lib/mysql -lmysqlclient

where /usr/include/mysql is the path to mysql.h and /usr/lib/mysql is the path to libmysqlclient.so. Enter

locate mysql.h

and

locate libmysqlclient.so

to find these paths.

#include <iostream>
#include <stdio.h>
#include <mysql.h>

int main() {

MYSQL mysql;
MYSQL_RES *pResult;
MYSQL_ROW row;

mysql_init(&mysql);

cout << "Connecting ... \n";

if (!mysql_real_connect(&mysql, "angie", "steve", "letmein", "mysql", 0, NULL, 0))
{

fprintf(stderr, "Failed to connect to database: Error: %s\n", mysql_error(&mysql));

}

cout << "Selecting data ... \n";

if (mysql_query(&mysql, "select User, Host from user"))
{

fprintf(stderr, "Failed to select from user table: Error: %s\n", mysql_error(&mysql));

}

pResult = mysql_store_result(&mysql);

if (!pResult)
{

fprintf(stderr, "Failed to store results: Error: %s\n", mysql_error(&mysql));

}

cout << "There are " << mysql_num_rows(pResult) << " users.\n";

while ((row = mysql_fetch_row(pResult)))
{

cout << "\t" << row[0] << "@" << row[1] << "\n";

}

cout << "Freeing memory used for the reult set ...\n";
mysql_free_result(pResult);

cout << "Closing ...\n";
mysql_close(&mysql);

cout << "Finishing ...\n";
return 0;

}