The answer about why you get error message was already answered by many users here. My answer is about how to fix and use it as it be.

Refer from this link.

    Open MySQL client (or MariaDB client). It is a command line tool.
    It will ask your password, enter your correct password.
    Select your database by using this command use my_database_name;

    Database changed

    set global innodb_large_prefix=on;

    Query OK, 0 rows affected (0.00 sec)

    set global innodb_file_format=Barracuda;

    Query OK, 0 rows affected (0.02 sec)