DataSource Controls :: Excluding Zero Numbers From The Query?

Is there any way, I can exclude the whole row if one particular column has zero in it. I have this query

select first_name, last_name , employee_num, cubeNumber, extension

from tblData left join tblfacility
ON tblData.employee_num = tblfacilit.employee_num
left join tblextension ext
on tblData.extension = ext.extension

tablExtension has phone number extension in it. If we don't know someones phone extension, we put zero for their extension, now there are tons of people who have zero extension.when I run this query, it returns same name lot of times with different cubeNumber so I get

Fisrt_name last_name employeenum cubeNumbae extension

a ax 1 12 0
a ax 1 13 0
a ax 1 14 0
b bx 2 12 0
b bx 2 13 0
b bx 2 14 0

Both emploee a and employee b extensions are zero in above case. I want both a and b to be displayed only once .Right now it is displaying them so many times with all the cubesNumber that have extension zero.