selecting random records inside a UDF - sql-server

Question

I'm writing a function in sql server 2012.
I came to know that we can not use RAND() or NEWID() functions in the select statement of a function in sql server.
My function goes like this:
CREATE FUNCTION Keywordsuggester (#userid INT)
returns #suggestor_tab TABLE (
keywordid INT,
keywordname VARCHAR(max),
keywordcategory VARCHAR(max))
AS
BEGIN
DECLARE #category_table TABLE
(
category_name VARCHAR(max),
category_id INT,
rownum INT
)
DECLARE #ID INT = 1
DECLARE #COUNT INT = 0
DECLARE #I INT = 1
INSERT INTO #category_table
SELECT kc.NAME,
kc.id,
k.NAME,
d.NAME,
Row_number()
OVER(
ORDER BY d.id ASC) AS rownum
FROM dtypes d
JOIN keywords k
ON d.NAME LIKE '%' + k.NAME + '%'
JOIN keywordscategory kc
ON k.categoryid = kc.id
WHERE d.userid = #userid
SELECT #count = rownum
FROM #category_table
WHILE #count > #I
BEGIN
INSERT INTO #suggestor_tab
SELECT TOP 5 kc.id,
k.NAME,
kc.NAME
FROM kwords k
JOIN #category_table ct
ON k.categoryid = ct.category_id
JOIN kwcategory kc
ON kc.NAME = ct.category_name
WHERE ct.rownum = #I
--Here I'm inserting top 5 records for each category into the suggestor_tab,instead I have to insert random 5 records for each category(i.e.,#I)
SET #I=#I + 1
--return
END
INSERT INTO #suggestor_tab
SELECT kc.id,
k.NAME,
kc.NAME
FROM kwords k
JOIN #category_table ct
ON k.categoryid = ct.category_id
JOIN kwcategory kc
ON kc.NAME = category_name
RETURN
END
How can I get random records for each category(i.e., #I in the while loop).
I tried the query like:
SELECT TOP 5 k.NAME
FROM kwords k
JOIN #category_table ct
ON k.category_id = ct.id
JOIN kwcategory kc
ON kc.NAME = category_name
WHERE ct.rownum = #I
ORDER BY Newid()
which throws an error like:
Invalid use of a side-effecting operator 'newid' within a function.
Is there anyway to do this?
Thanks in advance.

Answer 1

You cannot use Non-deterministic Funcions inside UDF.
Create a View and use it in order by
create view Random
as
select newid() as New_id
Change you select something like this.
SELECT TOP 5 k.NAME
FROM KWords k
JOIN #category_table ct
ON k.category_id = ct.id
JOIN kwcategory kc
ON kc.NAME = category_name
WHERE ct.rownum = #I
ORDER BY (SELECT new_id
FROM random)