Get once time a duplicate record (SQL) - sql

Question

SELECT DISTINCT A.LeaseID,
C.SerialNumber,
B.LeasedProjectNumber As 'ProjectNumber',
A.LeaseComment As 'LeaseContractComments'
FROM aLease A
LEFT OUTER JOIN aLeasedAsset B
ON a.LeaseID = B.LeaseID
LEFT OUTER JOIN aAsset C
ON B.LeasedProjectNumber = C.ProjectNumber AND B.PartID = C.aPartid
WHERE A.LeaseComment IS NOT NULL
I got this result from a query statement. But I don't want to get repeated the last column(Comments) for the 3 records in the second column.
I want for the values on the second column write once the repeated comment. Like a Group By

Answer 1

Alright, I'll take a stab at this. It's pretty unclear what exactly you're hoping for, but reading your comments, it sounds like you're looking to build a hierarchy of sorts in your table.
Something like this:
"Lease Terminated Jan 29, 2013 due to the event of..."
216 24914 87
216 724992 87
216 724993 87
"Other potential column"
217 2132 86
...
...
Unfortuantely, I don't believe that that's possible. SQL Server is pretty strict about returning a table, which is two-dimensional by definition. There's no good way to describe a hierarchy such as this in SQL. There is the hierarchyid type, but that's not really relevant here.
Given that, you only really have two options:
My preference 99% of the time, just accept the duplicates. Handle them in your procedural code later on, which probably does have support for these trees. Unless you're dealing with performance-critical situations, or if you're pulling back a lot of data (or really long comments), that should be totally fine.
If you're hoping to print this result directly to the user, or if network performance is a big issue, aggregate your columns into a single record for each comment. It's well-known that you can't have multiple values in the same column, for the very same reason as the above-listed result isn't possible. But what you could do, data and your own preferences permitting, is write an aggregate function to concatenate the grouped results into a single, comma-delimited column.
You'd likely then have to parse those commas out, though, so unless network traffic is your biggest concern, I'd really just do it procedural-side.

Answer 2

SELECT STUFF((SELECT DISTINCT ', ' + SerialNumber
FROM [vLeasedAsset]
WHERE A.LeaseID = LeaseID AND A.ProjectNumber = ProjectNumber
FOR XML PATH (''))
, 1, 1, '') AS SerialNumber, [ProjectNumber],
MAX(ContractComment) 'LeaseContractComment'
FROM [vLeasedAsset] A
WHERE ContractComment != ''
GROUP BY [ProjectNumber], LeaseID
Output:
SerialNumber
24914, 724993
23401, 720356
ProjectNumber
87
91