I had codeigniter app that was running well with PHP 5.6 on MAMP.
I got the latest version of MAMP Pro with the latest PHP 7.
Everything was fine, till I browsed to my CI app.
It wouldn't load!!
After a bit of troubleshooting, I figured that a small change had to be done in my
'dbdriver' => 'mysqli' to
'dbdriver' => 'mysqli' and everything worked smoothly thereafter!