Select multiple rows into one variable in SQL Query
SELECT ft.ThreadTitle AS Title,
fr.ReplyText + ' ' + ua2.Username + ' ' + ft.ThreadText + ' ' +
-- THIS NEXT LINE IS WHAT I WANT TO ACHIEVE:
(Select ReplyText from ForumReply Where ThreadID=ft.ThreadID)
-- THE ABOVE LINE HAVE MULTIPLE ROWS/VALUES THAT I WANT TO JOIN INTO ONE VARIABLE. HOW?
AS [Content],
ss.Domain,
ss.SiteID,
ft.ThreadID AS ObjectId
FROM dbo.ForumReply AS fr INNER JOIN
dbo.ForumThreads AS ft ON fr.ThreadID = ft.ThreadID INNER JOIN
dbo.User_Account AS ua1 ON ft.CreateByUserID = ua1.UserID INNER JOIN
dbo.User_Account AS ua2 ON fr.ReplyUserID = ua2.UserID INNER JOIN
dbo.SysT_Site AS ss ON ua1.SiteID = ss.SiteID
This query gives error: Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or 开发者_JAVA技巧when the subquery is used as an expression.
How do I rewrite this query to work so that I get all the values into one variable? The end result need to be a "View" that looks like this:
.ObjectID int
.Content (string with all text that exists in the Forumthread.threadText and forumReply.ReplyText)
.Domain string
.SiteID int
Building upon Martin's comment:
DECLARE @t TABLE (id int, ReplyText varchar(100))
INSERT INTO @t (id, ReplyText) VALUES (1, 'So Long,')
INSERT INTO @t (id, ReplyText) VALUES (2, 'And Thanks for')
INSERT INTO @t (id, ReplyText) VALUES (3, 'All the Fish!')
SELECT (SELECT replytext + ' ' FROM @t FOR XML PATH('')) AS CONTENT
You can assign to local variable this way.
SELECT @TempVariable = (SELECT replytext + ' ' FROM @t FOR XML PATH(''))
What you need is a string concat aggregate function, which sql server unfortunuatley does not include.
You can create your own though using .Net CLr function see here and here
I used STUFF:
SELECT
MyTable.Number AS Number,
(SELECT stuff(
(
select ', ' + x from (SELECT MyOtherTable.Name AS x FROM MyOtherTable WHERE MyOtherTable.ID = MyTable.ID) tb
FOR XML PATH('')
)
, 1, 2, ''))AS AllNames
FROM
MyTable
Result:
Number: AllNames:
1 Andrew, Carl
2 Bobby, Dave
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