[plug]

You'll be glad to hear that they've finally been removed since PHP 7.0 so slowly but surely they're being consigned to history.

And there seems to be much better awareness about the perils of mysql_* functions amongst PHP devs these days.

However, 5.6 is still in security support until 31st December 2018, so all that bad advice on SO and elsewhere is still relevant and lurking, waiting to be found by inexperienced devs.