where clause, case statement - sql

Question

I need to have the case statement shown below added to the main query so that it excludes members when different dates. How can I add it in? Thanks.
SELECT DISTINCT
PI.INDEX_VALUE,
LB.STATE,
UNIQUE_ID,
'AL',
'EN',
MBP.START_DATE,
ADD_MONTHS(MBP.START_DATE,12)
FROM dwteam.PATIENT_DETAILS PD
INNER JOIN dwteam.ADMIN_CLIENT AC
ON AC.CLIENT_ID = PD.CLIENT_ID
and AC.DELETED_BY is null
-- and AC.IS_ACTIVE =1
INNER JOIN dwteam.MEM_BENF_PROG MBP
ON MBP.MEMBER_ID = PD.PATIENT_ID
and MBP.DELETED_BY is null
INNER JOIN dwteam.BENF_PLAN_PROG BPP
ON BPP.BEN_PLAN_PROG_ID = MBP.BEN_PLAN_PROG_ID
INNER JOIN dwteam.BENEFIT_PROGRAM BPR
ON BPR.BENEFIT_PROGRAM_ID = BPP.BENEFIT_PROGRAM_ID
and BPR.DELETED_BY is null
left JOIN dwteam.PATIENT_INDEX PI
ON PI.PATIENT_ID=MBP.MEMBER_ID
AND PI.INDEX_ID in (10073,10071)
left join UHG_000613129.HFS_LOB_ID_XWALK LB
on trim(upper(replace(replace(AC.CLIENT_NAME,'C&S',''),'M&R','')))=trim(upper(STATE_DESC))
WHERE PROGRAM_NAME IN ('Healthy Pregnancy','High Risk Pregnancy')
AND (sysdate < ADD_MONTHS(MBP.START_DATE,12)
OR sysdate < ADD_MONTHS(MBP.END_DATE,12))
CASE WHEN MBP.CLOSURE_ID = 40 THEN MBP.END_DATE - 120
WHEN MBP.CLOSURE_ID IN (5,18,103) THEN MBP.END_DATE - 365
ELSE MBP.END_DATE - 270 END AS END_DATE

Answer 1

You can use a CTE to name an expression, and then use it for any purpose you want in the outer query.
I don't know all the details of your query but it should take the following form:
with
x as (
SELECT DISTINCT
PI.INDEX_VALUE,
LB.STATE,
UNIQUE_ID,
'AL',
'EN',
MBP.START_DATE,
ADD_MONTHS(MBP.START_DATE,12) as m1,
CASE WHEN MBP.CLOSURE_ID = 40 THEN MBP.END_DATE - 120
WHEN MBP.CLOSURE_ID IN (5,18,103) THEN MBP.END_DATE - 365
ELSE MBP.END_DATE - 270 END AS END_DATE1
FROM dwteam.PATIENT_DETAILS PD
JOIN dwteam.ADMIN_CLIENT AC ON AC.CLIENT_ID = PD.CLIENT_ID
AND AC.DELETED_BY is null
JOIN dwteam.MEM_BENF_PROG MBP ON MBP.MEMBER_ID = PD.PATIENT_ID
AND MBP.DELETED_BY is null
JOIN dwteam.BENF_PLAN_PROG BPP ON BPP.BEN_PLAN_PROG_ID
= MBP.BEN_PLAN_PROG_ID
JOIN dwteam.BENEFIT_PROGRAM BPR ON BPR.BENEFIT_PROGRAM_ID
= BPP.BENEFIT_PROGRAM_ID
AND BPR.DELETED_BY is null
left JOIN dwteam.PATIENT_INDEX PI ON PI.PATIENT_ID=MBP.MEMBER_ID
AND PI.INDEX_ID in (10073,10071)
left join UHG_000613129.HFS_LOB_ID_XWALK LB
on trim(upper(replace(replace(AC.CLIENT_NAME,'C&S',''),'M&R','')))
= trim(upper(STATE_DESC))
WHERE PROGRAM_NAME IN ('Healthy Pregnancy','High Risk Pregnancy')
AND (sysdate < ADD_MONTHS(MBP.START_DATE,12)
OR sysdate < ADD_MONTHS(MBP.END_DATE,12))
)
SELECT *
FROM x
WHERE end_date1 > ... -- filtering predicate(s) using a named expression
Tweak as necessary.