Go Premium for a chance to win a PS4. Enter to Win

x
?
Solved

liniking adjacent rows in MS Sql Server 2005 and Oracle 10g

Posted on 2014-12-29
8
Medium Priority
?
182 Views
Last Modified: 2015-01-23
I have a set of data and I want to create pairs from each adjacent row. Pairs are only relevant if they have the same id eg

ID, sequence, type
1, 1, a
1, 2, b
1, 3, c
2, 4, d
2, 5, e
2, 6, f

create a set of rows as follows
1,a,b
2,b,c
3,d,e
4,e,f
0
Comment
Question by:pcomb
  • 3
  • 2
  • 2
  • +1
8 Comments
 
LVL 78

Expert Comment

by:slightwv (䄆 Netminder)
ID: 40522771
This works for Oracle and should work for SQL Server.

I returned the sequence so it returns:
  SEQUENCE T N
---------- - -
         1 a b
         2 b c
         4 d e
         5 e f

Open in new window


Not 1,2,3,4.  In Oracle replacing the outer sequence with rownum will return 1,2,3,4.  Not sure what the SQL Server equivalent is.

select sequence, type, next_type from (
select sequence, type, lead(type) over(partition by id order by sequence) next_type
from tab1
)
where next_type is not null
/

Open in new window

0
 
LVL 49

Accepted Solution

by:
PortletPaul earned 2000 total points
ID: 40523046
>>"Pairs are only relevant if they have the same id"

I cannot follow how that statement works with the examples

there are 3 rows with an ID of 1, and 3 rows with an id of 2 making only 2 result rows

If the quote above is true; how on earth do you get any more than 2 rows as a result
0
 

Author Comment

by:pcomb
ID: 40523092
slightwv thank you this looks good. I got it working for Oracle but Sql Server 2005 does not support lead
0
Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.

 
LVL 49

Expert Comment

by:PortletPaul
ID: 40523457
Again i don't  follow. The results by slightwv don't  match those provided  in thee question.

Could you check the sample data and results please  or verify that  the results  by slightwv as re the correct  ones for the sample data .

Lead  isn't  available  until   mssql 2012 i believe. Its more complex but can be done - if i knew what  the results should be.
0
 

Author Comment

by:pcomb
ID: 40523470
PortletPaul slightwvs results do match except the sequence has gaps which is not critical it just needs to  be unique. The key part is to ahve the pairs eg a,b or b.c as rows

If you know a way to do this in sqlserver 2005 that would be great
 SEQUENCE T N
---------- - -
         1 a b
         2 b c
         4 d e
         5 e f

thanks
0
 
LVL 32

Expert Comment

by:awking00
ID: 40523634
This should work on both Oracle and SQL Server, with the caveat that SQL Server requires a subquery alias -
select row_number() over (order by sequence) newid, type1, type2 from
(select t1.id, t1.sequence, t1.type type1, t2.type type2
 from yourtable t1, yourtable t2
 where t1.id = t2.id
   and t1. sequence  + 1 = t2.sequence) as x  ==> "as x" is not needed for Oracle
;
0
 
LVL 32

Expert Comment

by:awking00
ID: 40523639
Perhaps I should have named the newid alias to newsequence instead, but the query will, in fact, return 1,2,3,4.
0
 
LVL 49

Expert Comment

by:PortletPaul
ID: 40525020
Nice cross-dbms solution awking00!

I would recommend  ANSI inner join syntax
SELECT
      ROW_NUMBER() OVER (ORDER BY sequence) NEWSEQENCE
    , type1
    , type2
FROM (
            SELECT
                  T1.id
                , T1.sequence
                , T1.type TYPE1
                , T2.type TYPE2
            FROM yourtable T1
                  INNER JOIN yourtable T2 ON T1.id = T2.id AND T1.sequence + 1 = T2.sequence
      ) X
;

Open in new window


(with that alias X just leave out "AS " and then it will work for both platforms)

no points please
0

Featured Post

What does it mean to be "Always On"?

Is your cloud always on? With an Always On cloud you won't have to worry about downtime for maintenance or software application code updates, ensuring that your bottom line isn't affected.

Question has a verified solution.

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

In this article we will learn how to fix  “Cannot install SQL Server 2014 Service Pack 2: Unable to install windows installer msi file” error ?
What if you have to shut down the entire Citrix infrastructure for hardware maintenance, software upgrades or "the unknown"? I developed this plan for "the unknown" and hope that it helps you as well. This article explains how to properly shut down …
Via a live example, show how to set up a backup for SQL Server using a Maintenance Plan and how to schedule the job into SQL Server Agent.
Via a live example, show how to setup several different housekeeping processes for a SQL Server.

916 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