Querying MySQL with C: A Rookie’s Guide

So, you want to do some database stuff with C? Cool! Let’s break it down step by step. We’re gonna talk about how to connect to a MySQL database and run some queries.

First Things First: Get Your Tools

You need to have MySQL and a C compiler installed on your computer. If you’re using Windows, you’ll probably want to install MySQL and a compiler like MinGW or something similar.

Include the Right Headers

In your C program, start by including the MySQL library headers. You can add this at the top of your code:

#include <mysql/mysql.h>
    

Connecting to the Database

Here’s the magic part. You need to create a connection to your MySQL server. This is basically like opening a door to your database. Here’s a code snippet to show how it’s done:

MYSQL *conn;
conn = mysql_init(NULL);
if (conn == NULL) {
    fprintf(stderr, "mysql_init() failed\n");
    return EXIT_FAILURE;
}

if (mysql_real_connect(conn, "host", "user", "password", "database", 0, NULL, 0) == NULL) {
    fprintf(stderr, "mysql_real_connect() failed\n");
    mysql_close(conn);
    return EXIT_FAILURE;
}
    

Replace “host”, “user”, “password”, and “database” with your actual database details!

Running a Query

Now that you’re connected, it’s time to run some SQL queries! Here’s how you can do it:

if (mysql_query(conn, "SELECT * FROM tablename")) {
    fprintf(stderr, "SELECT * failed. Error: %s\n", mysql_error(conn));
    mysql_close(conn);
    return EXIT_FAILURE;
}
    

Make sure to replace tablename with the actual table you want to query.

Fetching Results

After running a query, you’ll want to get the results back. Here’s a simple way to do that:

MYSQL_RES *res;
MYSQL_ROW row;

res = mysql_store_result(conn);
if (res == NULL) {
    fprintf(stderr, "mysql_store_result() failed. Error: %s\n", mysql_error(conn));
    mysql_close(conn);
    return EXIT_FAILURE;
}

while ((row = mysql_fetch_row(res)) != NULL) {
    printf("%s\n", row[0]); // Print first column
}

mysql_free_result(res);
    

Closing the Connection

Finally, don’t forget to close the connection when you’re done!

mysql_close(conn);
    

That’s It!

There you go! You just learned how to connect to a MySQL database and run a query using C. It might seem tricky at first, but with a little practice, you’ll get the hang of it. Happy coding!