How to apply order by on Update? - sql-server

Question

I am trying to update values in Temporary table but before update i want to order by the records on the basis of date.
UPDATE INS
set ins.PrefferedEmail = IC.CntcInfoTxt
From #Insured INS
Inner Join InsuredContact IC
on IC.InsuredId = INS.Insuredid and IC.ExpDt < Getdate() And (INS.InsuredStatus = 'Expired' or INS.InsuredStatus = 'Merged')
Where IC.CntcTypeCd = 'EML' and IC.InsuredId = #InsuredId and MAX(IC.ExpDt) ExpDt
I want to update on the basis of this column IC.ExpDt
Thanks in advance

Answer 1

I think you are confusing an UPDATE with SELECT(ing) the correct data to update with.
I solved this problem with a common table expression (cte) and the rank() function. The cte is a nice way to get a sub-query results. The rank is needed to find the most recent contact info.
-- 1 - Get id, contact text, expired date, with a rank by expired date
-- 2 - Join with table to update, select rank = 1
;
WITH cteRecentContactInfo
AS
(
SELECT
ic.InsuredId,
ic.CntcInfoTxt,
ic.ExpDt,
RANK() OVER (ORDER BY ic.ExpDt DESC) as RankByDt
FROM
InsuredContact as ic
WHERE
ic.CntcTypeCd = 'EML' and ic.ExpDt < getdate()
)
UPDATE ins
FROM #Insured ins INNER JOIN cteRecentContactInfo rci
ON ins.Insuredid = rci.Insuredid and ins.ExpDt = rci.ExpDt
WHERE
(ins.InsuredStatus = 'Expired' OR ins.InsuredStatus = 'Merged') AND
rci.RankByDt = 1

Answer 2

Update and sorting doesn't work that way. The rows are not necessarily stored in any particular order, so sorting and updating are completely independent.
If you only want to update based on MAX(ExpDt) you need a subquery that pulls that up.
UPDATE INS
SET INS.PrefferedEmail = tempOutside.CntcInfo
FROM (SELECT IC.CntcInfo,IC.InsuredID FROM
InsuredContact IC INNER JOIN
(SELECT MAX(IC.ExpDt) AS MaxExpDt,IC.InsuredID
FROM IC
WHERE IC.ExpDt < Getdate()
AND IC.CntcTypeCd = 'EML'
GROUP BY IC.InsuredID) AS tempInside
ON tempInside.InsuredID = IC.InsuredID
AND IC.ExpDt = tempInside.MaxExpDt) AS tempOutside
INNER JOIN INS ON tempOutside.InsuredID = INS.InsuredId
WHERE (INS.InsuredStatus = 'Expired' OR INS.InsuredStatus = 'Merged')
AND INS.InsuredID = #InsuredID
On unrelated notes, for the good of whoever is doing maintenance on your code you might want to consider fixing the spelling errors (e.g. should be Preferred instead of 'Preffered') and giving the tables more meaningful names. Also since you're only working with one ID from #InsuredID you could simplify the code and remove an inner join or two but what I have should work for updating several records at once not just the one selected by #InsuredID.

Answer 3

Thanks for your time and comments. I have done this and its working fine
UPDATE INS
set ins.PrefferedEmail = ICC.CntcInfoTxt
From #Insured INS
Inner Join
(
SELECT
InsuredId,
CntcInfoTxt,
CntcTypeCd
From InsuredContact ICC
Where ExpDt = (select MAX(ExpDt) from InsuredContact where ExpDt < GETDATE() and CntcTypeCd = 'EML' and InsuredId = 10)
) As ICC
on ICC.InsuredId = INS.InsuredId And (INS.InsuredStatus = 'Expired' or INS.InsuredStatus = 'Merged')
Where ICC.InsuredId = #InsuredId