how to use case with these 2 conditions null and doesnt exist?

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how to use case with these 2 conditions null and doesnt exist?

montserrat.deza

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June 23, 2017 at 12:34 pm

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Hello experts,
Im having difficulty to write these query with both options, these is what I have so far and is working in a SQL query:
case when sola.ECCN is null then icd.ECCN else sola.ECCN end AS TESTVALUEECCN
but how can I add the doesn't exist option??
I need to show this value icd.ECCN when this value sola.ECCN is null or doesnt exist.
Any help will be much much appreciate it

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Ed Wagner SSC Guru Points: 287026 More actions · Answer 1

montserrat.deza - Friday, June 23, 2017 12:34 PM
Hello experts,
Im having difficulty to write these query with both options, these is what I have so far and is working in a SQL query:
case when sola.ECCN is null then icd.ECCN else sola.ECCN end AS TESTVALUEECCN
but how can I add the doesn't exist option??
I need to show this value icd.ECCN when this value sola.ECCN is null or doesnt exist.
Any help will be much much appreciate it

It looks like you can replace your CASE statement with:

ISNULL(sola.ECCN, icd.ECCN) TestValueCCN

From your description of sola.ECCN not existing, I'm guessing you're OUTER JOINing sola to icd. This is only a guess. In that case, if the row in sola doesn't exist, it'll return NULL in the result set, so the NULL check (either CASE or ISNULL) will handle it.

If my guess is wrong, please post DDL and your full query so I can better see what you're working with.

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Lowell SSC Guru Points: 323506 More actions · Answer 2

can't you just add another WHEN THEN?
case when icd.ECCN is not null then icd.ECCN when sola.ECCN is not null then sola.ECCN else 'missing' end AS TESTVALUEECCN

that could also be written with a COALESCE, whihc is easier to read, but is still converted to the exact same case
COALESCE(icd.ECCN,sola.ECCN,'missing')

Lowell

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montserrat.deza Say Hey Kid Points: 695 More actions · Answer 3

Thank you!!! that is easy lol!!! Thank you so much will work...