DB connection Issue

[ebose]

Hello,

I downloaded your software, and installed it on a Debian Stretch, MySQL Ver 15.1 Distrib 10.1.26-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2.
mysqli extension is enabled in php.ini

My issue is like if the php could not connect the database.
I got some errors in logs as follow :
PHP Notice: Undefined variable: db in /srv/(path)

Finally, I can not insert, update or delete items of the address book.

Do you know this issue ?

Thank you.
Antoine