Conditionals in transact-sql select column lists - sql

Question

I've got a query that looks a bit like this:
select
records.id,
contacts.name + ' (' + contacts.organization + ')' as contact,
from records
left join contacts on records.contact = contacts.contactid
Problem is - contacts.organization is frequently empty, and I get contacts like "John Smith ()". Is there a way to only concatenate the organization if it's non-empty?

Answer 1

Use a CASE statement
SELECT
records.id,
CASE contacts.organization
WHEN '' THEN contacts.name
ELSE contacts.name + ' (' + contacts.organization + ')'
END as Contact
FROM records
LEFT JOIN contacts ON records.contact = contacts.contactid
You could modify it to also check for NULL values, but I do not believe you have that issue because if you had a NULL in your contacts.organization, your entire result field would be null instead of blank.

Answer 2

Not sure if this is the best way to do it:
CASE contacts.organization
WHEN '' THEN ''
ELSE '(' + contacts.organzation + ')' END

Answer 3

use a CASE, like CASE WHEN contacts.organization not null then ' (' + c.o + ') ' else '' end

Answer 4

You always need to expect nulls, because of your outer join:
select
records.id,
contacts.name + CASE WHEN contacts.organization IS NULL OR contacts.organization='' THEN '' ELSE ' (' + contacts.organization + ')' END as contact,
from records
left join contacts on records.contact = contacts.contactid

Answer 5

If you're dealing with NULL values there are some functions that specialize in them which are worth knowing.
ISNULL()
COALESCE()
NULLIF()
NULLIF() might be the one you're looking for. It basically takes two params. It returns the first param unless it is NULL, otherwise it returns the second.
Here's what I approximate your code would be:
select
records.id,
contacts.name + ISNULL(' (' + contacts.organization + ')', '') as contact,
from records
left join contacts on records.contact = contacts.contactid
Most NULL-related functions can be replaced by a larger CASE statement. CASE is your more general tool. But using specific functions will make your code cleaner, or at least more terse.