i tried to create index for that column(f_product) but it is  showing following error message.

Cannot create index on view dbo.V_PROD_ALIAS_MANU' because it contains one or more UNION, INTERSECT,...

This is the view query.It contains union all operator so not able to create index for this view.Is there any way to optimize this query?

CREATE VIEW...

Thank you very much.

I used below query to get the output.it is coming but i want to replace ROLEID in the query output.

select UR1.ApplicationID ,(select UR2.RoleID from UserRoles...

STRING_AGG function is not working in my SQL SERVER version(Microsoft SQL Server 2016 (SP1) (KB3182545)).Any other method to get the output?

CREATE TABLE USERROLES(ApplicationID int,Roleid INT)

Insert into userroles values(1,1);
insert into userroles values(1,5)
insert into userroles values(3,5)

Thank you.How to attach file?.I want to attach execution plan

if i use the same order of clustered index,i think it will improve.if i skip the first column,it decrease the performance.i have to use the existing index only,I cannot create...

No.I am not tested I am checking in db side now and i will test and tell u.

i made some changes in the query.actually i created clustered index for three columns for example
(column1,column2,column3) but i not used column1 in my where condition i used column2 and...