Programming Buddies,

Looking at the following links, can you be kind enough to tell me which one I should learn from and which one teaches what method (mysqli, pdo, etc.) and whether they are on php 7 or 5 because only looking for php 7:

[url]https://daveismyname.blog/blog/login-and-registration-system-with-php[/url]
[url]https://www.codeproject.com/articles/759094/step-by-step-php-tutorials-for-beginners-creating[/url]
[url]http://buildinternet.com/2009/12/creating-your-first-php-application-part-1[/url]

And, is this a good way to prevent sql injection ? It is unorthodox, I guess:

https://blogs.msdn.microsoft.com/brian_swan/2010/03/04/whats-the-right-way-to-prevent-sql-injection-in-php-scripts/