Best way to check if a CSV file contains only zeros (separated by comma)

I want to quickly identify files of this form (shape of the "matrix" can change)

0,0,0,0,0
0,0,0,0,0
0,0,0,0,0
0,0,0,0,0

What is the simplest way of doing it?

>Solution :

Try to match any character other than 0 or , with [^0,]. If that fails, the file only contains zeroes.

if ! grep -q '[^0,]' filename.csv
then
    echo file is all zeroes
fi