Multiple text updates to a single row

I have a table A that has related records in table B. I need to run an update to concatonate certian values in table B into a single value in table A.

Since an UPDATE can't update the same row twice, is there any way I can do this other than use a Cursor?

No need to use cursor. simple update should be enough, but you need to watch out for the data types though. You should be able to use somthing like this.

Code Snippet

declare @.a table (x int, y varchar(200))

declare @.b table (x int, i int, j char(2), k bit)

insert @.a select 1, NULL

insert @.a select 2, NULL

insert @.a select 3, NULL

insert @.a select 4, NULL

insert @.a select 5, NULL

insert @.b select 1, 55, 'AB', 0

insert @.b select 2, 66, 'CD', 1

insert @.b select 3, 77, 'EF', 1

insert @.b select 4, 88, 'GH', 0

insert @.b select 5, 99, 'IJ', 1

update a

set a.y = cast (b.i as varchar(10)) + b.j + cast (b.k as varchar(1))

from @.a a join @.b b

on a.x = b.x

select * from @.a

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Thank you for the response. Unfortunately, this is not my situation. I have multiple related records in table B that relate back to single records in table A. I'll update your code example to reflect the problem I have.

Code Snippet

declare @.a table (x int, y varchar(200))

declare @.b table (x int, j char(2))

insert @.a select 1, NULL

insert @.a select 2, NULL

insert @.b select 1, 'AB'

insert @.b select 1, 'CD'

insert @.b select 1, 'EF'

insert @.b select 2, 'ZY'

insert @.b select 2, 'RX'

--The Following select will fail to return

--concatonated values in a.y because the

--UPDATE can't update the same row value

--twice in the same UPDATE statement.

update a

set a.y = ISNULL(a.y,'') + b.j

from @.a a join @.b b

on a.x = b.x

--column y only holds the first value for

--group 1 and group 2

select * from @.a

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I am sure, there will be better ways than this code, you can do something like this.

Code Snippet

declare @.a table (x int, y varchar(200))

declare @.b table (x int, j char(2))

declare @.temp table (x int)

declare @.x int

declare @.y varchar(200)

insert @.a select 1, NULL

insert @.a select 2, NULL

insert @.b select 1, 'AB'

insert @.b select 1, 'CD'

insert @.b select 1, 'EF'

insert @.b select 2, 'ZY'

insert @.b select 2, 'RX'

insert @.temp

select distinct x from @.a

while exists (select 1 from @.temp)

begin

select top 1 @.x = x from @.temp

select @.y = ISNULL(@.y, '') + j from @.b b where b.x = @.x

select @.y as 'the value'

update a

set y = ISNULL(y, '') + @.y

from @.a a

where a.x = @.x

delete from @.temp where x = @.x

set @.y = ''

end

select * from @.a

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Here is an old post that should help. Basically, you create a udf to concatenate the values.

http://groups.google.com/group/microsoft.public.sqlserver.programming/browse_thread/thread/81da308504ac0e90

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Is this just for display? Or are you going to be storing the values like this? Best policy would be to use the UI to display the rows as you want. For display, you can use the techniques on the following page:

http://databases.aspfaq.com/general/how-do-i-concatenate-strings-from-a-column-into-a-single-row.html

But if you are doing this to store the values like this, it is a bad idea. Having each value in a different row is the best policy always. Far easier in SQL to build up a value than it is tear it apart.

set nocount on
declare @.a table (x int, y varchar(200))
declare @.b table (x int, j char(2))
insert @.a select 1, NULL
insert @.a select 2, NULL
insert @.b select 1, 'AB'
insert @.b select 1, 'CD'
insert @.b select 1, 'EF'
insert @.b select 2, 'ZY'
insert @.b select 2, 'RX'

update a
set y = LEFT(o.list, LEN(o.list)-1)
FROM @.a a
CROSS APPLY
(
SELECT
CONVERT(VARCHAR(12), j) + ',' AS [text()]
FROM
@.b s
WHERE
s.x = a.x
ORDER BY
x
FOR XML PATH('')
) o (list)

select *
from @.a

Returns:

x y

-- -

1 AB,CD,EF

2 ZY,RX

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First, thanks to Sankar and oj for your assistance.

Louis, your solution is what I was looking for. I do need to store the value, but it is for a very specific reason. I am finishing a table and stored procedure solution to delivering an open ended number of report subscription records to an SSIS package to output between 1 and 76 reports to PDF with a potentially different set of input parameters and values per client, per report.

Using the code above, I will be able to populate a single table structure with all report subscription records regardless of input parameters. I will concatenate the parameters as you illustrated above as "&parm1=val1&parm2=val2" while the next record may have "&parm5=value5" only. It allows me to run all filtered reports based on scheduling values (i.e. daily, weekly, monthly) while accounting for the differences in reports and client requirements.

I have not spent enough time exploring the XML functionality in SQL Server, and it bit me this time.

Thanks again for the help.

Hugh

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oj,

On second glance I used your UDF route. Made it easy to integrate into an existing sql insert without adding any more code to my stored procedure.

Thanks.