Eliminating NULL rows in TSQL query [duplicate] - tsql

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How to eliminate NULL fields in TSQL
I am using SSMS 2008 R2 and am developing a TSQL query. I want just 1 record / profile_name. Because some of these values are NULL, I am currently doing LEFT JOINS on most of the tables. But the problem with the LEFT JOINs is that now I get > 1 record for some profile_names!
But if I change this to INNER JOINs then some profile_names are excluded entirely because they have NULL values for these columns. How do I limit the query result to just one record / profile_name regardless of NULL values? And if there are non-NULL values then I want it to choose the record with non-NULL values. Here is initial query:
select distinct
gp.group_profile_id,
gp.profile_name,
gp.license_number,
gp.is_accepting,
case when gp.is_accepting = 1 then 'Yes'
when gp.is_accepting = 0 then 'No '
end as is_accepting_placement,
mo.profile_name as managing_office,
regions.[region_description] as region,
pv.vendor_name,
pv.id as vendor_id,
at.description as applicant_type,
dbo.GetGroupAddress(gp.group_profile_id, null, 0) as [Office Address],
gsv.status_description
from group_profile gp With (NoLock)
inner join group_profile_type gpt With (NoLock) on gp.group_profile_type_id = gpt.group_profile_type_id and gpt.type_code = 'FOSTERHOME' and gp.agency_id = #agency_id and gp.is_deleted = 0
inner join group_profile mo With (NoLock) on gp.managing_office_id = mo.group_profile_id
left outer join payor_vendor pv With (NoLock) on gp.payor_vendor_id = pv.payor_vendor_id
left outer join applicant_type at With (NoLock) on gp.applicant_type_id = at.applicant_type_id and at.is_foster_home = 1
inner join group_status_view gsv With (NoLock) on gp.group_profile_id = gsv.group_profile_id and gsv.status_value = 'OPEN' and gsv.effective_date =
(Select max(b.effective_date) from group_status_view b With (NoLock)
where gp.group_profile_id = b.group_profile_id)
left outer join regions With (NoLock) on isnull(mo.regions_id, gp.regions_id) = regions.regions_id
left join enrollment en on en.group_profile_id = gp.group_profile_id
join event_log el on el.event_log_id = en.event_log_id
left join people client on client.people_id = el.people_id
As you can see, the results of the above query is 1 row / profile_name:
group_profile_id profile_name license_number is_accepting is_accepting_placement managing_office region vendor_name vendor_id applicant_type Office Address status_description Cert Date2
But now watch what happens when I add in 2 LEFT JOINs and 1 additional column:
select distinct
gp.group_profile_id,
gp.profile_name,
gp.license_number,
gp.is_accepting,
case when gp.is_accepting = 1 then 'Yes'
when gp.is_accepting = 0 then 'No '
end as is_accepting_placement,
mo.profile_name as managing_office,
regions.[region_description] as region,
pv.vendor_name,
pv.id as vendor_id,
at.description as applicant_type,
dbo.GetGroupAddress(gp.group_profile_id, null, 0) as [Office Address],
gsv.status_description,
ri.[description] as race
from group_profile gp With (NoLock)
inner join group_profile_type gpt With (NoLock) on gp.group_profile_type_id = gpt.group_profile_type_id and gpt.type_code = 'FOSTERHOME' and gp.agency_id = #agency_id and gp.is_deleted = 0
inner join group_profile mo With (NoLock) on gp.managing_office_id = mo.group_profile_id
left outer join payor_vendor pv With (NoLock) on gp.payor_vendor_id = pv.payor_vendor_id
left outer join applicant_type at With (NoLock) on gp.applicant_type_id = at.applicant_type_id and at.is_foster_home = 1
inner join group_status_view gsv With (NoLock) on gp.group_profile_id = gsv.group_profile_id and gsv.status_value = 'OPEN' and gsv.effective_date =
(Select max(b.effective_date) from group_status_view b With (NoLock)
where gp.group_profile_id = b.group_profile_id)
left outer join regions With (NoLock) on isnull(mo.regions_id, gp.regions_id) = regions.regions_id
left join enrollment en on en.group_profile_id = gp.group_profile_id
join event_log el on el.event_log_id = en.event_log_id
left join people client on client.people_id = el.people_id
left join race With (NoLock) on el.people_id = race.people_id
left join race_info ri with (nolock) on ri.race_info_id = race.race_info_id
The above query results in all of the same profile_names, but some with NULL race values:
group_profile_id profile_name license_number is_accepting is_accepting_placement managing_office region vendor_name vendor_id applicant_type Office Address status_description Cert Date2 race
Unfortunately it complicates matters that I need to join in 2 additional tables for this one additional field value (race). If I simply change the last two LEFT JOINs above to INNER JOINs then I eliminate the NULL rows above. But I also eliminate some of the profile_names:
group_profile_id profile_name license_number is_accepting is_accepting_placement managing_office region vendor_name vendor_id applicant_type Office Address status_description Cert Date2 race
Hopefully I have provided all of the details that you need for this question.

Answer 1

Not the most elegant solution, but one that will work:
select [stuff]
from group_profile gp With (NoLock)
inner join group_profile_type gpt With (NoLock) on gp.group_profile_type_id = gpt.group_profile_type_id and gpt.type_code = 'FOSTERHOME' and gp.agency_id = #agency_id and gp.is_deleted = 0
inner join group_profile mo With (NoLock) on gp.managing_office_id = mo.group_profile_id
join payor_vendor pv on ISNULL(gp.payor_vendor_id, 'THISVALUEWILLNEVEROCCUR') = ISNULL(pv.payor_vendor_id, 'THISVALUEWILLNEVEROCCUR')
...etc...
Biggest issue with what I posted is that you'll be doing a whole lot of table scans.