Excluding rows derived from case statement with a specific value based on values from another column - sql

Question

How do I exclude rows with a specific value in a field based on specific values of another field? To dive deeper:
I have a column called "rule_name" that's derived from a case statement.
I have another column called "DeliveryTermsIdentifier" that's pulled from another table (see image of query result below).
I'm trying to remove rows with rule_name "Delivery event required" only if DeliveryTermsIdentifier is "PP", "DA", ect. I'm getting thrown off because my rule_name column is based off a condition already.
image of query result
Here is the SQL used to derive those 2 columns:
,case when s.ShipmentNo is not null then cast(dqr.rulename as varchar(30))
else cast(dqc.dataqualityruleid as varchar(30)) end as rule_name
,case when (dqd.SuccessFlag = 0) then 'Missing'
when (dqd.SuccessFlag = 1) then 'Reported'
when (s.ShipmentNo is null) then 'Missing' end reporting_result
,s.DeliveryTermsIdentifier
from CustomerMasterList cml
join organization o on o.organizationid = cml.senderid
inner join DataQualityConfig dqc on dqc.DomainId = cml.DomainID
left outer join shipment s on s.shipmentno = cml.shipmentno
left outer join dataqualityresult dqd on dqd.shipmentid = s.shipmentid
left outer join dataqualityrule dqr on dqr.dataqualityruleid
=dqd.dataqualityruleid

Answer 1

One way is to put what you have in a subquery and filter out with a where clause in the outer query. E.g.
SELECT rule_name, reporting_result, DeliveryTermsIdentifier
FROM
(SELECT 'X'
,case when s.ShipmentNo is not null then cast(dqr.rulename as varchar(30))
else cast(dqc.dataqualityruleid as varchar(30)) end as rule_name
,case when (dqd.SuccessFlag = 0) then 'Missing'
when (dqd.SuccessFlag = 1) then 'Reported'
when (s.ShipmentNo is null) then 'Missing' end reporting_result
,s.DeliveryTermsIdentifier
from CustomerMasterList cml
join organization o on o.organizationid = cml.senderid
inner join DataQualityConfig dqc on dqc.DomainId = cml.DomainID
left outer join shipment s on s.shipmentno = cml.shipmentno
left outer join dataqualityresult dqd on dqd.shipmentid = s.shipmentid
left outer join dataqualityrule dqr on dqr.dataqualityruleid
=dqd.dataqualityruleid ) AS sub
WHERE DeliveryTermsIdentifier NOT IN ('PP', 'DA') AND rule_name <> 'Delivery event required'

Answer 2

You can also encapsulate your case statements into an outer apply and use the alias like this:
SELECT * ,
rules.rule_name ,
RESULT.reporting_result ,
s.DeliveryTermsIdentifier
FROM CustomerMasterList cml
JOIN organization o ON o.organizationid = cml.senderid
INNER JOIN DataQualityConfig dqc ON dqc.DomainId = cml.DomainID
LEFT OUTER JOIN shipment s ON s.shipmentno = cml.shipmentno
LEFT OUTER JOIN dataqualityresult dqd ON dqd.shipmentid = s.shipmentid
LEFT OUTER JOIN dataqualityrule dqr ON dqr.dataqualityruleid = dqd.dataqualityruleid
OUTER APPLY ( SELECT CASE WHEN ( dqd.SuccessFlag = 0 ) THEN 'Missing'
WHEN ( dqd.SuccessFlag = 1 ) THEN 'Reported'
WHEN ( s.ShipmentNo IS NULL ) THEN 'Missing'
END reporting_result ) RESULT
OUTER APPLY ( SELECT CASE WHEN s.ShipmentNo IS NOT NULL THEN
CAST(dqr.rulename AS VARCHAR(30))
ELSE
CAST(dqc.dataqualityruleid AS VARCHAR(30))
END AS rule_name ) rules
WHERE s.DeliveryTermsIdentifier NOT IN ( 'PP', 'DA' )
AND rules.rule_name <> 'Delivery event required';