TSQL IN and NOT IN - tsql

Question

I have the below query that returns all diagnosis that do not have a '-829' value associated to them. The query does work but I think that I've made it harder than it should be. Is there a tidier way of doing this?
select distinct
c2.diagnosisn DiagnosisName,
a2.text CareLookup
from core_patdiagnosis c1
LEFT OUTER JOIN core_diagnosis c2 ON c1.diagnosis = c2.id
LEFT OUTER JOIN core_carecontext c3 ON c1.carecontex = c3.id
LEFT OUTER JOIN applookup_instance a1 ON c1.lkp_specialty = a1.id
LEFT OUTER JOIN core_diagnosis_taxonomyma c5 ON c2.id = c5.id
LEFT OUTER JOIN applookup_instance a3 ON c5.lkp_taxonomyna = a3.id
LEFT OUTER JOIN applookup_instance a2 ON c3.lkp_context = a2.id
where c2.id IN
(
select c11.id core_diagnosis_c1_id
from core_diagnosis c11
LEFT OUTER JOIN core_diagnosis_taxonomyma c21 ON c11.id = c21.id
LEFT OUTER JOIN applookup_instance a11 ON c21.lkp_taxonomyna = a11.id
WHERE
c11.isactive = 1
and a11.id != -829 or a11.id is null
)
AND
c2.id NOT IN
(
select c12.id ProcID
from core_procedure c12
LEFT OUTER JOIN core_procedure_taxonomyma c22 ON c12.id = c22.id
LEFT OUTER JOIN applookup_instance a12 ON c22.lkp_taxonomyna = a12.id
WHERE
c12.isactive = 1
and a12.id = -829 or a12.id is null
)
AND
c1.sys_creation_datetime > '01 Dec 2017 00:00:00' AND a2.text like
'%Emergency%'

Answer 1

extra stuff not used
a2.text like '%Emergency%' breaks the outer join
select distinct c2.diagnosisn DiagnosisName, a2.text CareLookup
from core_patdiagnosis c1
JOIN core_diagnosis c2 ON c2.id = c1.diagnosis
JOIN core_carecontext c3 ON c3.id = c1.carecontex
JOIN applookup_instance a2 ON a2.id = c3.lkp_context
where c2.id IN
( select c11.id
from core_diagnosis c11
LEFT OUTER JOIN core_diagnosis_taxonomyma c21 ON c11.id = c21.id
LEFT OUTER JOIN applookup_instance a11 ON c21.lkp_taxonomyna = a11.id
WHERE c11.isactive = 1 and a11.id != -829
or a11.id is null
)
AND
c2.id NOT IN
( select c12.id
from core_procedure c12
LEFT OUTER JOIN core_procedure_taxonomyma c22 ON c12.id = c22.id
LEFT OUTER JOIN applookup_instance a12 ON c22.lkp_taxonomyna = a12.id
WHERE c12.isactive = 1 and a12.id = -829
or a12.id is null
)
AND c1.sys_creation_datetime > '01 Dec 2017 00:00:00'
AND a2.text like '%Emergency%'

Answer 2

You could use a CTE (Common Table Expression - see msdn page):
WITH BufferTableCTE (id)
AS
(...)
SELECT ...
FROM ...
WHERE id in (SELECT id FROM BufferTableCTE WHERE id != -829)
AND NOT id in (SELECT id FROM BufferTableCTE WHERE id = -829)
AND ...
Another way would be to store an intermediate result in a temporary table and then use this temporary table later on (twice, once with id != -829 and once with id = 829)
Both ways would reduce your repeated sql declarations.