How to get the max date for multiple conditions - sql

Question

A bit new to Oracle specific SQL syntax, more familiar with MS SQL Server.
I'm having trouble with a join.
Specifically, the join is supposed to allow me to return the most recent date from a table. (In SQL Server I would just put select top 1 date order by date---with oracle it is confusing!)
Here is my entire query, I'm trying to return the max date for each of the date columns in the select statement with the MAX( prefix. (I know the max prefix isn't the correct syntax to get what I'm after, I'm just listing that here so you know which dates I need max date back on..) How do I get the most current date back for those columns?:
SELECT DISTINCT
req.LCR_REQUEST_ID "Request_ID"
,req.MATTER_ID AS "MatterID_lcr"
,req.CUSTOMER_NAME AS "AccountName_lcr"
,req.STATUS AS "CurrentContractStatus_lcr"
,MAX(HIS.RECORDED_DATE) AS "CurrentStatus_ChangeDate"
--,HIS.STATUS AS "ContractStatus_Historic_lcr"
,MAX(HIS_SUB.RECORDED_DATE) AS "Submitted_Status_Date"
--,HIS_NA.RECORDED_DATE AS "NotAssigned_Status_Date"
,MAX(HIS_AtA.RECORDED_DATE) AS "AssignedToAttorney_Status_Date"
,MAX(HIS_SCIN.RECORDED_DATE) AS "InNegotiation_Status_Date"
,MAX(HIS_EXE.RECORDED_DATE) AS "Executed_Status_Date"
,MAX(HIS_CONV.RECORDED_DATE) AS "ConverteToAmend_Status_Date"
,MAX(HIS_DEAD.RECORDED_DATE) AS "Dead_Status_Date"
,MAX(HIS_COMP.RECORDED_DATE) AS "Completed_Status_Date"
,MAX(HIS_EXP.RECORDED_DATE) AS "Expired_Status_Date"
,CASE
WHEN req.DEALSIZE = 0 THEN ''
WHEN req.DEALSIZE = 1 THEN 'Less Than 100K'
when req.DEALSIZE = 2 THEN '100K-500K'
when req.DEALSIZE = 3 THEN '500K-1M'
when req.DEALSIZE = 4 THEN '1M-10M'
when req.DEALSIZE = 5 THEN '>10M'
END
AS "DealSize_lcr"
,cm_out.PTY_NAME AS "AccountName_cm"
,cm_out.PTY_ID AS "PTYID_CM"
,req.customer_id "PtyID_lcr"
,cm_out.EFFECTIVE_DATE "EffDate_lcr"
,cm_out.INITIALTERM_END_DATE "CPEDate_lcr"
,cm_out.CONTRACT_TERMINATION_DATE "FCTDate_lcr"
,cm_out.TERM_NOTICE_NONCOMP_REASON "ReasonForTermination_lcr"
,cm_out.TERM_TYPE "TermType_lcr"
,cm_out.INITIALTERM_DURATION "InitialTerm_lcr"
,cm_out.INVOICE_TIMEMEAS "InitialTermTymeMeas_lcr"
,cm_out.NUMBER_OF_RENEWALS "NumberOfRenewals_lcr"
,req.AMENDMENT "ParentMatterID_lcr"
,prod.rpg "RPG_lcr"
,prod.SALES_PRODUCT_NAME "Product_lcr"
,prod.CONTRACT_TYPE "ContractType_lcr"
,req.CONTRACT_ROLE "ContractRole_lcr"
,cm_out.METADATA_FLAG "MetaFlag_lcr"
,CASE
WHEN cm_out.DATA_AUTO_IMPORT_YN = 1 THEN 'YES'
WHEN cm_out.REQUESTOR = 'Imported Record' THEN 'YES'
ELSE 'NO'
END
"DataImport_lcr"
,CASE act.actionstatus
WHEN 'Cancel Date Update' THEN 'Yes'
ELSE NULL
END "ActionToCancelAutoDate_lcr"
,req_emp.FIRST_NAME || ' ' || req_emp.LAST_NAME "Requestor_lcr"
,att_emp.FIRST_NAME || ' ' || att_emp.LAST_NAME "Attorney_lcr"
,req.REQUESTOR_DEPARTMENT "Requestor_Department_lcr"
,req.AGREEMENT_TITLE "AgreementTitle_lcr"
,req.DATE_RECORDED
FROM LCR_REQUEST REQ
LEFT JOIN LCR_ACTION ACT ON req.MATTER_ID = act.MATTER_ID
LEFT JOIN CM_CONTRACT_OUTBOUND cm_out ON cm_out.MATTER_ID = NVL(req.MATTER_ID,req.AMENDMENT)
LEFT JOIN LCR_REQUEST_PRODUCT prod_REQ ON prod_req.LCR_REQUEST_ID = req.LCR_REQUEST_ID
LEFT JOIN LCR_PRODUCT PROD ON prod.PRODUCT_ID = prod_req.PRODUCT_ID
LEFT JOIN LCR_EMPLOYEE att_emp ON req.ASSIGNED_TO = att_emp.ORACLE_PERSON_ID
LEFT JOIN LCR_EMPLOYEE req_emp ON req.REQUESTED_BY_ID = req_emp .ORACLE_PERSON_ID
LEFT JOIN LCR_STATUS_HISTORY HIS ON HIS.LCR_REQUEST_ID = req.LCR_REQUEST_ID AND ((HIS.STATUS = REQ.STATUS) OR (HIS.STATUS = 'Assigned to Attorney' AND REQ.STATUS = 'Assigned To Attorney'))
--LEFT JOIN LCR_STATUS_HISTORY HIS_NA ON req.LCR_REQUEST_ID = HIS_NA.LCR_REQUEST_ID AND HIS_NA.STATUS = 'Not Assigned'
LEFT JOIN LCR_STATUS_HISTORY HIS_AtA ON req.LCR_REQUEST_ID = HIS_AtA.LCR_REQUEST_ID AND HIS_AtA.STATUS = 'Assigned to Attorney'
LEFT JOIN LCR_STATUS_HISTORY HIS_SUB ON req.LCR_REQUEST_ID = HIS_SUB.LCR_REQUEST_ID AND HIS_SUB.STATUS = 'Submitted'
LEFT JOIN LCR_STATUS_HISTORY HIS_SCIN ON req.LCR_REQUEST_ID = HIS_SCIN.LCR_REQUEST_ID AND HIS_SCIN.STATUS = 'Submission Complete-In Negotiation'
LEFT JOIN LCR_STATUS_HISTORY HIS_EXE ON req.LCR_REQUEST_ID = HIS_EXE.LCR_REQUEST_ID AND HIS_EXE.STATUS = 'Executed'
LEFT JOIN LCR_STATUS_HISTORY HIS_CONV ON req.LCR_REQUEST_ID = HIS_CONV.LCR_REQUEST_ID AND HIS_CONV.STATUS = 'Converted to amendment.'
LEFT JOIN LCR_STATUS_HISTORY HIS_DEAD ON req.LCR_REQUEST_ID = HIS_DEAD.LCR_REQUEST_ID AND HIS_DEAD.STATUS = 'Dead'
LEFT JOIN LCR_STATUS_HISTORY HIS_COMP ON req.LCR_REQUEST_ID = HIS_COMP.LCR_REQUEST_ID AND HIS_COMP.STATUS = 'Completed'
LEFT JOIN LCR_STATUS_HISTORY HIS_EXP ON req.LCR_REQUEST_ID = HIS_EXP.LCR_REQUEST_ID AND HIS_EXP.STATUS = 'Expired/Terminated'
WHERE REQ.CATEGORY_NAME = 'Sales'
AND
REQ.DATE_RECORDED BETWEEN to_date ('07/01/2012', 'mm/dd/yyyy') AND to_date ('06/30/2013','mm/dd/yyyy')
GROUP BY
req.LCR_REQUEST_ID
,req.MATTER_ID
,req.CUSTOMER_NAME
,req.STATUS
,HIS.RECORDED_DATE
--,HIS.STATUS
,HIS_SUB.RECORDED_DATE
--,HIS_NA.RECORDED_DATE
,HIS_AtA.RECORDED_DATE
,HIS_SCIN.RECORDED_DATE
,HIS_EXE.RECORDED_DATE
,HIS_CONV.RECORDED_DATE
,HIS_DEAD.RECORDED_DATE
,HIS_COMP.RECORDED_DATE
,HIS_EXP.RECORDED_DATE
,CASE
WHEN req.DEALSIZE = 0 THEN ''
WHEN req.DEALSIZE = 1 THEN 'Less Than 100K'
when req.DEALSIZE = 2 THEN '100K-500K'
when req.DEALSIZE = 3 THEN '500K-1M'
when req.DEALSIZE = 4 THEN '1M-10M'
when req.DEALSIZE = 5 THEN '>10M'
END
,cm_out.PTY_NAME
,cm_out.PTY_ID
,req.customer_id
,cm_out.EFFECTIVE_DATE
,cm_out.INITIALTERM_END_DATE
,cm_out.CONTRACT_TERMINATION_DATE
,cm_out.TERM_NOTICE_NONCOMP_REASON
,cm_out.TERM_TYPE
,cm_out.INITIALTERM_DURATION
,cm_out.INVOICE_TIMEMEAS
,cm_out.NUMBER_OF_RENEWALS
,req.AMENDMENT
,prod.rpg
,prod.SALES_PRODUCT_NAME
,prod.CONTRACT_TYPE
,req.CONTRACT_ROLE
,cm_out.METADATA_FLAG
,CASE
WHEN cm_out.DATA_AUTO_IMPORT_YN = 1 THEN 'YES'
WHEN cm_out.REQUESTOR = 'Imported Record' THEN 'YES'
ELSE 'NO'
END
,CASE act.actionstatus
WHEN 'Cancel Date Update' THEN 'Yes'
ELSE NULL
END
,req_emp.FIRST_NAME || ' ' || req_emp.LAST_NAME
,att_emp.FIRST_NAME || ' ' || att_emp.LAST_NAME
,req.REQUESTOR_DEPARTMENT
,req.AGREEMENT_TITLE
,req.DATE_RECORDED;

Answer 1

I wonder how you get multiple columns with a max date using a single TOP 1?
Most of the LEFT JOINs to LCR_STATUS_HISTORY can easily be replaced by a single join using MAX(CASE):
LEFT JOIN
(
SELECT LCR_REQUEST_ID,
MAX(CASE WHEN STATUS = 'Assigned to Attorney' THEN RECORDED_DATE END) AS "AssignedToAttorney_Status_Date"
,MAX(CASE WHEN STATUS = 'Submission Complete-In Negotiation' THEN RECORDED_DATE END) AS "InNegotiation_Status_Date"
,...
FROM LCR_STATUS_HISTORY
GROUP BY LCR_REQUEST_ID
) his
ON HIS.LCR_REQUEST_ID = req.LCR_REQUEST_ID
Then you probably don't need the GROUP BY any more.
And in this join-condition the OR-part can be removed:
((HIS.STATUS = REQ.STATUS) OR (HIS.STATUS = 'Assigned to Attorney' AND REQ.STATUS = 'Assigned To Attorney'))
ON HIS.LCR_REQUEST_ID = req.LCR_REQUEST_ID