?
Solved

Controlling JOIN Hierarchy in SQL2000 without CTE

Posted on 2008-06-23
6
Medium Priority
?
681 Views
Last Modified: 2010-10-05
I am joining on a set of data in SQL2000, and would like to control the hierarchy of which JOIN is used when given a choice of matches.

I can assign a numeric value to the data set, so I only need to JOIN on the lowest/highest number available.

So for example on the below if joining on the middle column with B, I would want to return 250, not another value.

1     A    150
1     B     250
2     A     330
2     B     558
3     A     554
3     B     447
3     C     557
0
Comment
Question by:rickchild
[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
  • 3
  • 2
6 Comments
 
LVL 17

Expert Comment

by:dbaSQL
ID: 21845402
possibly just use MIN or MAX in your select?
0
 
LVL 18

Assisted Solution

by:lludden
lludden earned 150 total points
ID: 21845562
SELECT P1 FROM T1 INNER JOIN (SELECT ColB, MIN(ColC) FROM Table2 GROUP BY ColB) T2 ON T1.ColB = T2.ColB
0
 
LVL 17

Accepted Solution

by:
dbaSQL earned 600 total points
ID: 21845573
i used TOP instead of MIN/MAX.  i'm not sure if this is what you're looking for:

create table test (one int, two char(1), three int)
insert test
select  1,'A',150
union
select 1,'B',250
union
select 2,'A',330
union
select 2,'B',558
union
select 3,'A',554
union
select 3,'B',447
union
select 3,'C',557

select * from test

select TOP 1 a.one,a.two,a.three from test a inner join test b
on a.one = b.one
where a.two = 'b'
group by a.one,a.two,a.three
0
Nothing ever in the clear!

This technical paper will help you implement VMware’s VM encryption as well as implement Veeam encryption which together will achieve the nothing ever in the clear goal. If a bad guy steals VMs, backups or traffic they get nothing.

 
LVL 13

Author Comment

by:rickchild
ID: 21863459
lludden: I will try youtr solution now

dbaSQL: Your solutions is fairly similar to mine, but the problem I am having is that I am trying to use this query to join onto another table, and I seem unable to pass in the 'b' from the first table.

I either need to pass in the Code to the WHERE, or be able to work on the hierarchy when I join it to the main table


LEFT JOIN
(
    SELECT TOP 1 * FROM
    (
	SELECT * FROM
	(
		SELECT 1 as Orders, Entity, Code, Description from revenuereporting..tbl_DIMProduct
		WHERE Entity = 'ASL' and Code = L.[Product Name]
		UNION
		SELECT 2 as Orders, Entity, Code, Description from revenuereporting..tbl_DIMProduct
		WHERE Entity = 'Inc' and Code =  L.[Product Name]
	) AS FFFF
    ) as FF
) as F
ON L.[Product Name] = F.Code

Open in new window

0
 
LVL 13

Author Comment

by:rickchild
ID: 21863551
PS.  This will work if I pass in the Code as a variable, but I am in SSRS so struggling to get that to work.
0
 
LVL 13

Author Comment

by:rickchild
ID: 21863912
Think I may have sussed this now using a subquery generated column, rather than joining on a subquery.

The hierarchy just depends on the order of the UNION, which is ok for this case.
select a.*, (
		select top 1 Description FROM
		(
		SELECT Code, Description
		FROM revenuereporting..tbl_DIMProduct
		WHERE Entity = 'ASL' and Code = a.Code
		UNION ALL 
		SELECT Code, Description
		FROM revenuereporting..tbl_DIMProduct
		WHERE Entity = b.Entity and Code = a.Code
		) as Description
	) as Description

Open in new window

0

Featured Post

Will your db performance match your db growth?

In Percona’s white paper “Performance at Scale: Keeping Your Database on Its Toes,” we take a high-level approach to what you need to think about when planning for database scalability.

Question has a verified solution.

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

In part one, we reviewed the prerequisites required for installing SQL Server vNext. In this part we will explore how to install Microsoft's SQL Server on Ubuntu 16.04.
Ready to get certified? Check out some courses that help you prepare for third-party exams.
This video shows how to set up a shell script to accept a positional parameter when called, pass that to a SQL script, accept the output from the statement back and then manipulate it in the Shell.
Via a live example, show how to setup several different housekeeping processes for a SQL Server.

719 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