?
Solved

SQL update column via loop

Posted on 2008-10-01
7
Medium Priority
?
775 Views
Last Modified: 2010-08-05
Simple really

Need to update a column's value, by appending 1 to a counter and adding a string to it ...

SQL code should explain it all ...
-- Grab the max ext_ref_id and add one.
DECLARE @MAX_EXT_REF_ID AS INTEGER
 
SELECT @MAX_EXT_REF_ID = MAX(CAST(REPLACE(EXT_REF_ID, '_BLC', '') AS INTEGER)) + 1 
FROM [TBL_BLUECARE_CANDIDATES] 
WHERE [EXT_REF_ID] like '%_BLC'
 
SELECT @MAX_EXT_REF_ID -- RETURNS 78656
 
 
--SELECT ALL USERS THAT DO NOT HAVE '_BLC' in the [EXT_REF_ID]
SELECT [EXT_REF_ID]
FROM   [TBL_BLUECARE_CANDIDATES]
WHERE  [EXT_REF_ID] not like '%_BLC'
ORDER BY [EXT_REF_ID]
 
/* RETURNS DATA LIKE 
 
000
0001
001
002
003003003
007
01
079091
10661
11101110
11986
121212123
12335
1234
 
*/
 
 
-- NEED TO UPDATE ALL [EXT_REF_ID] WITHOUT '_BLC' and APPEND @MAX_EXT_REF_ID + 1 + '_BLC'
--  eg. 78656_BLC
--  eg. 78657_BLC
--  eg. 78658_BLC
--  eg. 78659_BLC
 
BEGIN LOOP 
	FOR EACH RECORD IN QUERY ABOVE
	UPDATE [EXT_REF_ID] = (@MAX_EXT_REF_ID + 1) + '_BLC'
END LOOP

Open in new window

0
Comment
Question by:kloner
[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
  • 4
  • 2
7 Comments
 
LVL 39

Assisted Solution

by:BrandonGalderisi
BrandonGalderisi earned 150 total points
ID: 22614780
Try this....

After you see if it works, remove the begin tran/rollback.
begin tran
DECLARE @MAX_EXT_REF_ID AS INTEGER
 
SELECT @MAX_EXT_REF_ID = MAX(CAST(REPLACE(EXT_REF_ID, '_BLC', '') AS INTEGER)) + 1 
FROM [TBL_BLUECARE_CANDIDATES] 
WHERE [EXT_REF_ID] like '%_BLC'
 
;with theRef as(
SELECT [EXT_REF_ID],row_number() over(order by [ext_Ref_id]) + @Max_ext_ref_id as rn
FROM   [TBL_BLUECARE_CANDIDATES]
WHERE  [EXT_REF_ID] not like '%_BLC')
 
update bcc
set ext_ref_id = cast(rn as varchar(16))+'_BLC'
from [tbl_bluecare_candidates] bcc
join theRef r
on bcc.ext_ref_id = r.ext_ref_id
 
select * from [tbl_bluecare_candidates]
 
rollback

Open in new window

0
 

Author Comment

by:kloner
ID: 22614943
I forgot to mention ... some of the existing [EXT_REF_ID] data that we are trying to update actually contains dulpicate data ... hence we can't rely on the join statement you suggested ... on bcc.ext_ref_id = r.ext_ref_id

.......

Current output dump:

000
000
0001
001
001
001
002
003003003
007
01
079091
10661
11101110
11986
11986
0
 
LVL 39

Expert Comment

by:BrandonGalderisi
ID: 22614968
So 001, 001, 001 would all need to be new records.  What is the PK of the table?
0
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.

 

Author Comment

by:kloner
ID: 22615164
Well you won't believe this ... ther's no bloody PK in this OLD DB ... I can just get the duplicate records and manually update them hey as a quick win ...
0
 
LVL 39

Expert Comment

by:BrandonGalderisi
ID: 22615426
You should add an identity column and make it your PK.  I assume you don't have a clustered index either?
0
 
LVL 39

Expert Comment

by:BrandonGalderisi
ID: 22615433
It seems like that's what you are trying to do with the ext_ref_id.
0
 
LVL 27

Accepted Solution

by:
Zberteoc earned 225 total points
ID: 22616739
Here:
-- max value variable
DECLARE 
	@MAX_EXT_REF_ID int
 
-- get max value !!! WITHOUT ADDING 1 !!!
SELECT 
	@MAX_EXT_REF_ID = MAX(CAST(REPLACE(EXT_REF_ID, '_BLC', '') AS int)) 
FROM 
	[TBL_BLUECARE_CANDIDATES] 
WHERE 
	[EXT_REF_ID] like '%_BLC'
 
 
-- insert the distinct wanted [EXT_REF_ID] in a temp table
SELECT DISTINCT  
	[EXT_REF_ID]
INTO #aux
FROM   
	[TBL_BLUECARE_CANDIDATES] bc
WHERE  
	[EXT_REF_ID] not like '%_BLC'
ORDER BY
	[EXT_REF_ID]
 
-- add an identity column
ALTER TABLE #aux ADD id int identity
 
-- replace the [EXT_REF_ID] using the identity and @MAX_EXT_REF_ID
UPDATE bc SET
	[EXT_REF_ID]=id+@MAX_EXT_REF_ID
FROM
	[TBL_BLUECARE_CANDIDATES] bc
	INNER JOIN #aux a
		on a.[EXT_REF_ID]=bc.[EXT_REF_ID]

Open in new window

0

Featured Post

10 Questions to Ask when Buying Backup Software

Choosing the right backup solution for your organization can be a daunting task. To make the selection process easier, ask solution providers these 10 key questions.

Question has a verified solution.

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

This article will describe one method to parse a delimited string into a table of data.   Why would I do that you ask?  Let's say that you need to pass multiple parameters into a stored procedure to search for.  For our sake, we'll say that we wa…
Data architecture is an important aspect in Software as a Service (SaaS) delivery model. This article is a study on the database of a single-tenant application that could be extended to support multiple tenants. The application is web-based develope…
This tutorial will teach you the special effect of super speed similar to the fictional character Wally West aka "The Flash" After Shake : http://www.videocopilot.net/presets/after_shake/ All lightning effects with instructions : http://www.mediaf…
Sometimes it takes a new vantage point, apart from our everyday security practices, to truly see our Active Directory (AD) vulnerabilities. We get used to implementing the same techniques and checking the same areas for a breach. This pattern can re…

800 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