Can I filter based on new column created

Question

Can I add a where clause based on the new column r_text.
I only need to output the records when count of the query in the select is 0. Thus do I need to add in the where clause eg where r_text <> ''. The problem is r_text is not a valid coulumn in the database.
select
distinct a.style_id, b.sty, b.season, a.cust, a.ad_d, b.code,
(case when b.code = 'MAKE' then
(select min(t.value) from sn.age r, sn.text t
where r.t_id = '18' and r.name = 'MTGNSL'
and r.t_id = t.t_id
and r.name = t.name and r.text_id = t.text_id
and r.id_1 = a.id
) end) r_text,
(case when b.code is null then 'Blank Code'end) err

Answer 1

1) I'm not seeing a FROM clause in your inner query
2) I'm pretty sure that you don't want the clause WHERE <> ''. Oracle treats '' as NULL and nothing is ever equal to or unequal to NULL.
SELECT *
  FROM (<<any query>>)
WHERE <<any column>> <> ''will never return a row. I'm guessing that you want to say
WHERE r_text IS NOT NULLJustin
Distributed Database Consulting, Inc.
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