Solved

T-SQL Query needed for double-level string concatination from a single table

Posted on 2010-11-09
14
232 Views
Last Modified: 2012-05-10
For Microsoft SQL Server 2005 T-SQL I'm having difficulty writing a query that concatenates two-levels such as Compact Disc discs and tracks (see table below).

My best attempt is using XML as a vehicle for string concatenation as described here.

Using a single query without a server-side cursor I'd like to generate a report of my music collection like below with one concatenated line output per database row per album.  Once I figure out the query I'll add the appropriate HTML as a detail.

OUTPUT ROW 1:

Album 1
  Disc 1
    1. She Loves You
    2. Yellow Submarine

  Disc 2
    1. Revolution
    2. Long and Winding Road
    3. Hey Jude


OUTPUT ROW 2:

Album 2
  Disc 1
    ...


OUTPUT ROW 3:

Album 3
  Disc 1
     ....

  Disc 2
    .....
create table Song (
  AlbumID int,
  DiscNbr tinyint,
  TrackNbr tinyint,
  Song varchar(50)
)

Open in new window

0
Comment
Question by:ZuZuPetals
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 7
  • 5
  • 2
14 Comments
 
LVL 3

Expert Comment

by:expert_dharam
ID: 34095404
Did u tried this..

select AlbumID, STUFF(
      (SELECT  ',' + a.Song  AS [text()]
      from Song  a
      where a.AlbumID = b.AlbumID
      Order by a.Song
      for xml PATH('')),1,1,''      ) AS Comments_Concatenated
 from Song b
group by AlbumID
ORDER BY AlbumID
0
 
LVL 2

Author Comment

by:ZuZuPetals
ID: 34095689
Yes, but that's one level.
0
 
LVL 3

Expert Comment

by:expert_dharam
ID: 34095933
Here you go..

SELECT AlbumID, DiscNbr,

STUFF(
      (SELECT  ', ' + cast(a.TrackNbr as varchar) + '.' + a.Song  AS [text()]
      FROM Song  a
      WHERE a.AlbumID = b.AlbumID and a.DiscNbr = b.DiscNbr
      Order by a.Song
      FOR XML PATH('')),1,1,''      ) AS Songs
      
      
 FROM Song b
group by AlbumID,DiscNbr
ORDER BY AlbumID,DiscNbr
0
NFR key for Veeam Backup for Microsoft Office 365

Veeam is happy to provide a free NFR license (for 1 year, up to 10 users). This license allows for the non‑production use of Veeam Backup for Microsoft Office 365 in your home lab without any feature limitations.

 
LVL 2

Author Comment

by:ZuZuPetals
ID: 34097195
Thanks expert_dharam... that's a partial solution: that creates one row per disc.    Now I'm trying to caress it to roll up all discs of an album to a single row.
0
 
LVL 51

Expert Comment

by:Mark Wills
ID: 34099464
How about something like :


select ',' + 'Album '+convert(varchar,a.albumid) + ',' +
       'Disc '+convert(varchar,a.Discnbr) +
       (select ',' + convert(varchar,Tracknbr) + '.' + Song
        from song b where a.albumid = b.albumid and a.discnbr = b.discnbr for xml path('')) as [text()]
from (select distinct albumid, Discnbr from song) a  
for xml path('')
0
 
LVL 51

Expert Comment

by:Mark Wills
ID: 34099476
Think I might be misunderstanding your output requirement... Treated it as one long concatenated string.

Thats not quite what you are after - is it...

0
 
LVL 51

Expert Comment

by:Mark Wills
ID: 34099553
What about....


select listing
from (
      select albumid,0 as discnbr, 0 as tracknbr, 'Album '+convert(varchar,albumid) as listing from song group by albumid
      union
      select albumid,discnbr, 0 as tracknbr, '     Disc '+convert(varchar,Discnbr) as listing from song group by albumid, discnbr
      union
      select albumid,discnbr, tracknbr, '          '+convert(varchar,tracknbr)+'. '+song as listing from song
     )s
order by albumid,discnbr, tracknbr


0
 
LVL 2

Author Comment

by:ZuZuPetals
ID: 34105602
@mark_wills: The first one concatenates to a single string and the second one does no concatenation.  Still looking for something in between (one row per album), but I appreciate the attempts.
0
 
LVL 51

Expert Comment

by:Mark Wills
ID: 34106926
Right, knew I was misunderstanding :D

how about :

select 'Album '+convert(varchar,a.albumid) +
       (select ','+'Disc '+convert(varchar,Discnbr) +',' + convert(varchar,Tracknbr) + '.' + Song
        from song b where a.albumid = b.albumid for xml path('')) as [text()]
from (select distinct albumid from song) a  
0
 
LVL 2

Author Comment

by:ZuZuPetals
ID: 34113510
@mark_willis: Wow, that's really close.  The only bad thing is that it repeats the disc number for every track.
0
 
LVL 2

Author Comment

by:ZuZuPetals
ID: 34113560
My solution that I implemented is to use XML/text() to encapsulate the "tracks per disc" concatenation into a view for simplicity and readability.  I then use that view in a second XML/text() to concatenate the "discs per album" into a single string.  It takes 10 minutes to run on a million records but produces the exact result specified in the problem statement.  Thanks for everyone's help.
0
 
LVL 51

Accepted Solution

by:
Mark Wills earned 500 total points
ID: 34113837
Ah well... Good to hear you got your solution...

FWIW here is my last attempt (it is a challenge now) :)


select 'Album '+convert(varchar,a.albumid) +
    (select ','+'Disc '+convert(varchar,D.Discnbr) +
        (select ',' + convert(varchar,Tracknbr) + '.' + Song from song b where a.albumid = b.albumid and d.Discnbr=b.Discnbr for xml path(''))
    from song d where a.albumid=d.albumid group by d.discnbr for xml path(''))
from (select distinct albumid from song) a
0
 
LVL 2

Author Comment

by:ZuZuPetals
ID: 34114895
Awesome!!! That's it!  You did it Mark!  Thanks!

The only thing I added was order by DiscNbr,TrackNbr to get the ordering 1, 2, 3, etc. ascending.
0
 
LVL 2

Author Closing Comment

by:ZuZuPetals
ID: 34114898
YOU ROCK!
0

Featured Post

The Eight Noble Truths of Backup and Recovery

How can IT departments tackle the challenges of a Big Data world? This white paper provides a roadmap to success and helps companies ensure that all their data is safe and secure, no matter if it resides on-premise with physical or virtual machines or in the cloud.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

In this article I will describe the Backup & Restore method as one possible migration process and I will add the extra tasks needed for an upgrade when and where is applied so it will cover all.
Ever needed a SQL 2008 Database replicated/mirrored/log shipped on another server but you can't take the downtime inflicted by initial snapshot or disconnect while T-logs are restored or mirror applied? You can use SQL Server Initialize from Backup…
In an interesting question (https://www.experts-exchange.com/questions/29008360/) here at Experts Exchange, a member asked how to split a single image into multiple images. The primary usage for this is to place many photographs on a flatbed scanner…

740 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question