query result as comma-separated list

Hi,
I'n in an environment where I cannot make stored procedures. Now I need
to make a query with a subquery in the SELECT part which gives a comma
separated list of results:

SELECT
p.id,
listFunction(SELECT name FROM names WHERE name_parent=p.id) AS
'nameList'
FROM projects AS p

This query should return something like:
1, "john,mike,petra"
2, " bob,carl,sandra,pete
r,
etc

listFunction is (of course) not (yet) defined. Is this possible without
the use of stored procedures?
Mike

insomniux (mike.bosschaert@hccnet.nl)  writes:
> I'n in an environment where I cannot make stored procedures. Now I need
> to make a query with a subquery in the SELECT part which gives a comma
> separated list of results:
>
> SELECT
>    p.id,
>    listFunction(SELECT name FROM names WHERE name_parent=p.id) AS
> 'nameList'
> FROM projects AS p
>
> This query should return something like:
> 1, "john,mike,petra"
> 2, " bob,carl,sandra,pete
r,
> etc
>
> listFunction is (of course) not (yet) defined. Is this possible without
> the use of stored procedures?

In SQL 2000, it is actually not possible even with stored procedures
yo write such a function. You will have to write an iterative
solution that iterates over the table, and which uses a temp table
to aggregate the columns.

In SQL2005 you can do this in a single query, thanks to some of the
new XML stuff in SQL 2005.

--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techin.../2000/books.asp

I know there are various aggregate functions for numeric columns (like
min, max, ...). Wouldn't it be possible to write an aggregate function
for string-type columns which would enable to write the query as:

SELECT
p.id,
(SELECT listFunction(name) FROM names WHERE name_parent=p.id GROUP
BY name_parent) AS
'nameList'
FROM projects AS p

Erland Sommarskog  wrote:
> insomniux (mike.bosschaert@hccnet.nl) writes: 
need 
 comma
 
 without[color=darkre
d] 
>
> In SQL 2000, it is actually not possible even with stored procedures
> yo write such a function. You will have to write an iterative
> solution that iterates over the table, and which uses a temp table
> to aggregate the columns.
>
> In SQL2005 you can do this in a single query, thanks to some of the
> new XML stuff in SQL 2005.
>
> --
> Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se
>
> Books Online for SQL Server SP3 at
> http://www.microsoft.com/sql/techin.../2000/books.asp

Hi

If this is for a client to display the information, then the best place to
do this would be on the client itself.

John

"insomniux" <mike.bosschaert@hccnet.nl> wrote in message
news:1114361846.034822.103940@f14g2000cwb.googlegroups.com...
> Hi,
> I'n in an environment where I cannot make stored procedures. Now I need
> to make a query with a subquery in the SELECT part which gives a comma
> separated list of results:
>
> SELECT
>   p.id,
>   listFunction(SELECT name FROM names WHERE name_parent=p.id) AS
> 'nameList'
> FROM projects AS p
>
> This query should return something like:
> 1, "john,mike,petra"
> 2, " bob,carl,sandra,pete
r,
> etc
>
> listFunction is (of course) not (yet) defined. Is this possible without
> the use of stored procedures?
> Mike
>

I have access to a webinterface which I can feed with SQL, but some
statements are blocked.
I would prefer to create the statement in pure SQL but I think this is
not possible. I know how to get the first and the last value (using top
1 and sorting), but most subqueries return more than 3 rows. I know it
is possible to put all these values in separate columns, but the SQL
statements will become somewhat terrible.

insomniux wrote:

> Hi,
> I'n in an environment where I cannot make stored procedures. Now I need
> to make a query with a subquery in the SELECT part which gives a comma
> separated list of results:
>
> SELECT
>    p.id,
>    listFunction(SELECT name FROM names WHERE name_parent=p.id) AS
> 'nameList'
> FROM projects AS p
>
> This query should return something like:
> 1, "john,mike,petra"
> 2, " bob,carl,sandra,pete
r,
> etc
>
> listFunction is (of course) not (yet) defined. Is this possible without
> the use of stored procedures?
> Mike

This *should* be very easy to do in your client, looking up the appropriate
functions may be much faster than trying to force it into SQL.  The precise
steps you want to be able to execute are (in pseudocode):

// step 1, execute the query in whatever syntax your
// client language uses
//
$some_query = query_command("select ....")

// step 2, pluck out the values of one column to an array,
// your client should have some function for this
//
$some_array =  extract_column($some
_query,"ColumnA");

// step 3, in PHP the function is "implode", you want a function
// that collapses an array into a delimited string
//
$some_list = implode(",",$some_array);

Best of luck, HTH.

--
Kenneth Downs
Secure Data Software, Inc.
 (Ken)nneth@(Sec)ure(
Dat)a(.com)

insomniux (mike.bosschaert@hccnet.nl)  writes:
> I know there are various aggregate functions for numeric columns (like
> min, max, ...). Wouldn't it be possible to write an aggregate function
> for string-type columns which would enable to write the query as:

No, you cannot write your own aggregate functions in SQL 2000.

In SQL 2005 you can - using a CLR language. However, as I understand it,
it does not work very well for this case, at least not if you want the
lists to be ordered.


--
Erland Sommarskog, SQL Server MVP, esquel@sommarskog.se

Books Online for SQL Server SP3 at
http://www.microsoft.com/sql/techin.../2000/books.asp

Kenneth Downs wrote in  message
> insomniux wrote:
> 
>
> This *should* be very easy to do in your client, looking up the appropriat
e
> functions may be much faster than trying to force it into SQL.  The precis
e
> steps you want to be able to execute are (in pseudocode):
>
> // step 1, execute the query in whatever syntax your
> // client language uses
> //
> $some_query = query_command("select ....")
>
> // step 2, pluck out the values of one column to an array,
> // your client should have some function for this
> //
> $some_array =  extract_column($some
_query,"ColumnA");
>
> // step 3, in PHP the function is "implode", you want a function
> // that collapses an array into a delimited string
> //
> $some_list = implode(",",$some_array);
>
> Best of luck, HTH.

Unfortunately my client application does not allow me to use this kind
of syntax. Only SQL.
Thanks

"insomniux" <mike.bosschaert@hccnet.nl> wrote in message news:1114367673.194349.232680@g14g
2000cwa.googlegroups.com...
>I know there are various aggregate functions for numeric columns (like
> min, max, ...). Wouldn't it be possible to write an aggregate function
> for string-type columns which would enable to write the query as:
>
> SELECT
>    p.id,
>    (SELECT listFunction(name) FROM names WHERE name_parent=p.id GROUP
> BY name_parent) AS
> 'nameList'
> FROM projects AS p
>


Yes, it would.  The engineers at iAnywhere (SQL Anywhere) figured this one o
ut nearly a decade ago...

SELECT list( [distinct] expression )
FROM tablename

is their aggregate on strings.  You can even order the list (in addition to 
ordering the entire result set), and specify
custom delimiter characters (if you don't like commas).

www.ianywhere.com

-Paul Horan-
Sr. Architect
VCI  Springfield, Mass

"insomniux" <mike.bosschaert@hccnet.nl> wrote in message
news:1114361846.034822.103940@f14g2000cwb.googlegroups.com...
> Hi,
> I'n in an environment where I cannot make stored procedures. Now I need
> to make a query with a subquery in the SELECT part which gives a comma
> separated list of results:
>
> SELECT
>   p.id,
>   listFunction(SELECT name FROM names WHERE name_parent=p.id) AS
> 'nameList'
> FROM projects AS p
>
> This query should return something like:
> 1, "john,mike,petra"
> 2, " bob,carl,sandra,pete
r,
> etc
>
> listFunction is (of course) not (yet) defined. Is this possible without
> the use of stored procedures?
> Mike
>

This is a function I use to do what you describe.  I found the function
someplace on the Internet (don't remember where).  Maybe you can modify it
for your use.

DECLARE @NbrList VarChar(300)
Declare @InvoiceID Varchar(30)

SELECT @NbrList = COALESCE(@NbrList + ', ', '') +
CAST(C.TRACKING_NO AS varchar(30))

FROM         dbo.SHIPPER S INNER JOIN
dbo.SHIPPER_LINK SL ON S.PACKLIST_ID = SL.PACKLIST_ID
INNER JOIN
dbo.CARTON_LINE CL ON SL.CARTON_ID = CL.CARTON_ID AND
SL.CARTON_LINE_NO = CL.LINE_NO INNER JOIN
dbo.CARTON C ON CL.CARTON_ID = C.ID
WHERE S.INVOICE_ID = @InvoiceID
SELECT @NbrList
GO

Kevin