C++ Program to connect with MySQL - c++

Question

I am new to C++ (although I have some experience with C) and MySQL and I am trying to make a program that reads a database from MySQL, I have been following this tutorial but I get an error when I try to 'build' the solution. (I am using Visual C++ 2008 just like they do in the tutorial.
Compiling...
test2.cpp
c:\users\rafael\documents\visual studio 2008\projects\test2\test2\test2.cpp(43) : warning C4244: 'initializing' : conversion from 'my_ulonglong' to 'unsigned int', possible loss of data
Compiling manifest to resources...
Microsoft (R) Windows (R) Resource Compiler Version 6.0.5724.0
Copyright (C) Microsoft Corporation. All rights reserved.
Linking...
test2.obj : error LNK2019: unresolved external symbol _mysql_close#4 referenced in function _main
test2.obj : error LNK2019: unresolved external symbol _mysql_fetch_row#4 referenced in function _main
test2.obj : error LNK2019: unresolved external symbol _mysql_num_rows#4 referenced in function _main
test2.obj : error LNK2019: unresolved external symbol _mysql_store_result#4 referenced in function _main
test2.obj : error LNK2019: unresolved external symbol _mysql_query#8 referenced in function _main
test2.obj : error LNK2019: unresolved external symbol _mysql_real_connect#32 referenced in function _main
test2.obj : error LNK2019: unresolved external symbol _mysql_init#4 referenced in function _main
C:\Users\*****\Documents\Visual Studio 2008\Projects\test2\Debug\test2.exe : fatal error LNK1120: 7 unresolved externals
I followed the tutorial and I cannot figure out what's going on, I guess it's something to do with the linkers, but I do not know what could I do.
This is the code I am using (source):
#include "stdafx.h"
#include "my_global.h" // Include this file first to avoid problems
#include "mysql.h" // MySQL Include File
#define SERVER "localhost"
#define USER "root"
#define PASSWORD "********"
#define DATABASE "test"
int main()
{
MYSQL *connect; // Create a pointer to the MySQL instance
connect=mysql_init(NULL); // Initialise the instance
/* This If is irrelevant and you don't need to show it. I kept it in for Fault Testing.*/
if(!connect) /* If instance didn't initialize say so and exit with fault.*/
{
fprintf(stderr,"MySQL Initialization Failed");
return 1;
}
/* Now we will actually connect to the specific database.*/
connect=mysql_real_connect(connect,SERVER,USER,PASSWORD,DATABASE,0,NULL,0);
/* Following if statements are unneeded too, but it's worth it to show on your
first app, so that if your database is empty or the query didn't return anything it
will at least let you know that the connection to the mysql server was established. */
if(connect){
printf("Connection Succeeded\n");
}
else{
printf("Connection Failed!\n");
}
MYSQL_RES *res_set; /* Create a pointer to recieve the return value.*/
MYSQL_ROW row; /* Assign variable for rows. */
mysql_query(connect,"SELECT * FROM TABLE");
/* Send a query to the database. */
unsigned int i = 0; /* Create a counter for the rows */
res_set = mysql_store_result(connect); /* Receive the result and store it in res_set */
unsigned int numrows = mysql_num_rows(res_set); /* Create the count to print all rows */
/* This while is to print all rows and not just the first row found, */
while ((row = mysql_fetch_row(res_set)) != NULL){
printf("%s\n",row[i] != NULL ?
row[i] : "NULL"); /* Print the row data */
}
mysql_close(connect); /* Close and shutdown */
return 0;
}

Answer 1

Yes, it totally is a linker problem: it is almost surely missing the mysql library. In the project settings you should add the name (and the path) of the .lib you intend to use.