left join ZIPCODETABLE ta on ta.Zip like '%co.Zip%'

left join ZIPCODETABLE ta on ta.Zip = co.Zip
where ta.Zip LIKE '_%-'

set zipcode = left(zipcode, 5)
where right(ltrim(rtrim(zipcode)),1) = '-'

select
c.email
, c.firstName
, c.zip
, left(ta.zip,5) as zipMatch
, ta.zip as zipFullMatch
from CustomerDE c
left join ZIPCODETABLE ta on (left(ta.Zip,5) = left(c.zip,5))