SQL - Select latest max date when NVARCHAR column -


i want select latest input database.

currently gives me comments if i'm filtering using max

simplified version of query

select      a.[id],     ud.[name],     max(convert(date, an.[postedon])) 'date',     cast(an.[content] nvarchar(max)) 'comment'      [dbo].[account]  left join       [dbo].[userdata] ud on a.[userid] = ud.userid left join      [dbo].[note] on ud.[userid] = an.[customerid] group     a.[id], ud.[name], cast(an.[content] nvarchar(max))

current result

+---------+------------------------+------------+-------+ |id       |name                    |date        |comment| +---------+------------------------+------------+-------+ |01       |john                    |2017-08-15  |blue   | |01       |john                    |2017-07-10  |green  | |02       |bob                     |2017-07-15  |green  | |02       |bob                     |2017-06-05  |red    | |03       |eric                    |2017-08-15  |yellow | |04       |karl                    |2017-08-15  |null   | |04       |karl                    |2017-06-10  |black  | +---------+------------------------+------------+-------+

expected/desired result:

+---------+------------------------+------------+-------+ |id       |name                    |date        |comment| +---------+------------------------+------------+-------+ |01       |john                    |2017-08-15  |blue   | |02       |bob                     |2017-07-15  |green  | |03       |eric                    |2017-08-15  |yellow | |04       |karl                    |2017-08-15  |null   | +---------+------------------------+------------+-------+

fyi if remove cast(an.[content] nvarchar(max)) 'comment' query, don't see 'duplicates' name/id anymore (but no comment then)

any idea?

use row_number():

select t.* (select . . .,              row_number() on (partition a.id order convert(date, an.[postedon]) desc) seqnum       [dbo].[account] left join            [dbo].[userdata] ud            on a.[userid] = ud.userid left join            [dbo].[note]            on ud.[userid] = an.[customerid]      ) t seqnum = 1;

the . . . list of columns want.

as note: query not filtering maximum value. query calculating maximum value using aggregation query. important understand difference between filtering , aggregating.


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