Adding 'and' at the end of a comma separated list - sql

Question

Currently, I'm using the stuff function to create a comma separated list per each row.
x,y,z
What I want is to add commas for n-1 items in the list, with the final item being preceded by 'and'
x,y, and z.
For these purposes, just checking row number won't work because this list is being generated per unique Id, therefore I can't just iterate to the end of the table. Code below:
SELECT DISTINCT (sw.OwnerID)
,stuff((
SELECT DISTINCT ', ' + e.pn
FROM fct.enrtablev e
WHERE sw.OwnerID = e.OwnerId
FOR XML PATH('')), 1, 1, '') AS [Pet(s)]

Answer 1

A bit of a hack... AND string_agg() would be a better fit if 2017+
Here we use test the row_number() of the item count sum(1) over(), when equal this is the last item in the list
Example
Declare #YourTable table (OwnerID int,pn varchar(50))
Insert Into #YourTable values
(1,'X')
,(1,'Y')
,(1,'Z')
,(1,'Z')
,(2,'Apples')
Select Distinct
OwnerID
,stuff( ( Select case when row_number() over(order by pn) = nullif(sum(1) over() ,1)
then ', and '
else ', '
end + pn
FROM (Select distinct pn
From #YourTable
Where OwnerID = A.OwnerId
) e
Order By PN
For XML Path('')), 1, 2, '') AS [Pet(s)]
From #YourTable A
Returns
OwnerID Pet(s)
1 X, Y, and Z
2 Apples

Answer 2

XQUery and XML data model is based on ordered sequences. Exactly what we need.
Here is a simple solution based on XQuery and its FLWOR expression.
SQL
-- DDL and sample data population, start
DECLARE #tbl TABLE (OwnerID int, pn VARCHAR(50));
INSERT INTO #tbl (OwnerID, pn) VALUES
(1,'X'),
(1,'Y'),
(1,'Z'),
(2,'Apples');
-- DDL and sample data population, end
SELECT p.OwnerID
, (SELECT *
FROM #tbl AS c
WHERE c.OwnerID = p.OwnerID
FOR XML PATH('r'), TYPE, ROOT('root')
).query('
for $x in /root/r/pn/text()
return if ($x is (/root/r[last()]/pn/text())[1]) then
if (count(/root/r) gt 1) then concat("and ", $x) else string($x)
else concat($x, ",")
').value('.', 'VARCHAR(MAX)') AS Result
FROM #tbl AS p
GROUP BY p.OwnerID;
Output
+---------+----------------+
| OwnerID | Result |
+---------+----------------+
| 1 | X, Y, and Z |
| 2 | Apples |
+---------+----------------+

Answer 3

You can achieve this using ORDER BY and count.
Declare #YourTable table (OwnerID int,pn varchar(50))
Insert Into #YourTable values
(1,'X')
,(1,'Y')
,(1,'Z')
,(2,'Apples')
;WITH CTE_OwnerIdRank as
(
SELECT ownerid, pn, row_number() over (order by ownerId) as totalrn,
count(*) over(partition by ownerid order by ownerid) as ownercnt
from #yourtable
)
SELECT distinct OwnerId,
stuff((
SELECT ', ' + CASE WHEN c.totalrn = c.ownercnt then CONCAT(' and ',c.pn) else c.pn end
FROM CTE_OwnerIdRank as c
WHERE c.OwnerID = o.OwnerId
order by c.totalrn
FOR XML PATH('')), 1, 1, '') AS [Pet(s)]
from #yourtable as o
OwnerId
Pet(s)
1
X, Y, and Z
2
Apples