Excluding results with an empty value for a field

Question

For the query below, some results have nothing in the database for "age." How can I exclude these values that have nothing for "age"?

$sqlStr3 = "SELECT
                 username 
                 ,loginid
                 ,age  

        FROM login
        ORDER BY age ASC
           LIMIT $offset, $rowsperpage";

Answer 1

If age defaults to NULL (the typical case), add a simple WHERE age NOT NULL check:

SELECT
   username 
   ,loginid
   ,age  

FROM login
WHERE age NOT NULL
ORDER BY age ASC
LIMIT $offset, $rowsperpage

Answer 2

You could use a Where clause but it's easier and faster to just add the IS NOT NULL operator to your SELECT for that field.

$sqlStr3 = "SELECT
                 username 
                 ,loginid
                 ,age IS NOT NULL

        FROM login
        ORDER BY age ASC
           LIMIT $offset, $rowsperpage";

Comparison Functions and Operators