Count the number of columns populated in a row

Question

I have a table of this style in sql:

id	FirstName	LastName	Age
1	John	Williams	25
2	Anne		23

I want to count the number of columns filled in each row, as shown below.

id	FirstName	LastName	Age	PopulatedColumns
1	John	Williams	25	4
2	Anne		23	3

Does anyone know how to make a script that does this count in sql? But I didn't want to specify the name of the columns, because I have a very large table and it is not practical to put the name of all the columns. Is there a way to do this agnostic? Without putting names?

Answer 1

IN MySQL, you can use arithmetic:

select t.*,
       ( (id is not null) + (firstname is not null) + (lastname is not null) + (age is not null)
       ) as populated_columns
from t;