include, include_once, require or require_once?

php include
Ibrahim Azhar Armar picture Ibrahim Azhar Armar · Aug 23, 2010 · Viewed 41.4k times · Source

I have PHP file where I have defined the server access variables as well as the mysql_connect and mysql_select_db, as this functions are regularly used in almost every page in backend, while I am using include() which is perfectly working for me now, which method or function would you suggest and I would like to know if there is any flaw if I use include() or is it safe to use it?

Edit : Keeping in mind I'll be using $_SESSION variable too.

Answer

Sasha Chedygov picture Sasha Chedygov · Aug 23, 2010

The only difference between the two is that require and its sister require_once throw a fatal error if the file is not found, whereas include and include_once only show a warning and continue to load the rest of the page. If you don't want PHP to attempt to load the rest of your page without the database info (which I would assume), then use require_once. You don't need to include the file more than once, so there is no need to use the regular require function.

Related questions

Difference between require, include, require_once and include_once?

In PHP: When should I use require vs. include? When should I use require_once vs. include_once?

Read More
Get absolute path of initially run script

I have searched high and low and get a lot of different solutions and variables containing info to get the absolute path. But they seem to work under some conditions and not under others. Is there one silver bullet way …

Read More
How do I run a file on localhost?

How do I actually run a file on localhost? I know it is working, but how do I run a file on it, and how do I verify that the file is in fact running on localhost? Server newbie here, …

Read More