Fatal error: Call to undefined method mysqli_result::fetch_all()

mysqli_result::fetch_all() requires MySQL Native Driver (mysqlnd).

chances are you might be missing it.

have a look at this posts, that might help you.

mysqli fetch_all() not a valid function?

fetch_all consumes more memory than fetch_array() and has other detrimental side effects, so instead of fixing fetch_all, it's better to use fetch_array or fetch_assoc.

Detailed from PHP documentation:

Available only with mysqlnd.

As mysqli_fetch_all() returns all the rows as an array in a single step, it may consume more memory than some similar functions such as mysqli_fetch_array(), which only returns one row at a time from the result set. Further, if you need to iterate over the result set, you will need a looping construct that will further impact performance. For these reasons mysqli_fetch_all() should only be used in those situations where the fetched result set will be sent to another layer for processing.

If you really want to use it, you have to install mySQL with native drive (mysqlnd) Example installation:

./configure --with-mysql=mysqlnd \
--with-mysqli=mysqlnd \
--with-pdo-mysql=mysqlnd \

On Ubuntu you can just do

sudo apt-get install php5-mysqlnd

http://www.php.net/manual/en/mysqli-result.fetch-all.php

Available only with mysqlnd.

Notes about enabling mysqlnd: http://www.php.net/manual/en/mysqlnd.install.php