I think I see what you are trying to do.
You probably need to re-think your table structure
Your members table doesn't need the naics number columns
Create a new table 'membernaics' with the following columns..
membernaicsid, (PK, auto)
say, member 1 has naics 7, 8 and 9
the data would be
membernaicsid : memberid : naicsid
to retrieve the naicstitle for each member
SELECT member, naicstitle FROM members JOIN members ON membernaics.memberid = membernaics.memberid JOIN naics ON membernaics.naicsid = naics.naicstitle
This also allows you to have as many naics items per member as you wish