Re: [Q] Conditions in the column expression?

Ano Nymus wrote:

> I have a table t with columns n and m of type VARCHAR. I
> want to retrieve the entire n column, but I want the entries
> to be ordered such that those entries where m is null come
> first. As pseudo-code:
>
> SELECT n, (IF m IS NULL THEN 0 ELSE 1) AS c
> FROM t
> ORDER BY c, n;
>
> Moreover, I want to retrieve all those entries of n whose
> length is greater than 5, but I want NULL values for all
> those entries whose length is less or equal than 5. In
> pseudo-code:
>
> SELECT (IF LENGTH(m) <= 5 THEN NULL ELSE m)
> FROM t;
>
> How do I do this in Oracle?

SELECT n
FROM t
ORDER BY m NULLS FIRST;

-- 
Daniel Morgan
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