Att använda en CTE för att dela upp resultat över ett CROSS APPLY

Du kanske letar efter något sånt här (det är en förenklad version, jag använde bara förnamn och comment_date som "identifierare"). Jag testade det med hjälp av dessa data och - för tillfället - avbildning av max len 50 för att dela textkolumn. Tips:ändra comment_text datatype till VARCHAR(500)

DECLARE @Comments TABLE
(
    id INT NOT NULL IDENTITY PRIMARY KEY CLUSTERED,
    comment_date DATETIME NOT NULL,
    first_name VARCHAR(50) NOT NULL,
    last_name VARCHAR(50) NOT NULL,
    comment_title VARCHAR(50) NOT NULL,
    comment_text VARCHAR(500)
);

    INSERT INTO @Comments VALUES(CURRENT_TIMESTAMP, 'Bob', 'Example','Bob''s Comment', 'Text of Bob''s comment.');
    INSERT INTO @Comments VALUES(CURRENT_TIMESTAMP, 'Alice', 'Example','Alice''s Comment'
    , 'Text of Alice''s comment that is much longer and will need to be split over multiple rows aaaaaa bbbbbb cccccc ddddddddddd eeeeeeeeeeee fffffffffffff ggggggggggggg.');

WITH CTE AS (SELECT comment_date, first_name, '<Note>'+CAST( SUBSTRING(comment_text, 1, 50) AS VARCHAR(500)) +'</Note>'comment_text, 1 AS RN
             FROM @Comments 
             UNION ALL 
             SELECT A.comment_date, A.first_name, '<Text>'+CAST( SUBSTRING(A.comment_text, B.RN*50+1, 50) AS VARCHAR(500)) +'</Text>'AS comment_text, B.RN+1 AS RN
             FROM @Comments A 
             INNER JOIN CTE B ON A.comment_date=B.comment_date AND A.first_name=B.first_name 
            WHERE  LEN(A.comment_text) > B.RN*50+1                    
             )
SELECT A.comment_date, A.first_name, '<title>'+ comment_title+'</title>' AS markup  
FROM @Comments A
UNION ALL
SELECT B.comment_date, B.first_name, B.comment_text AS markup  
FROM  CTE B ;

Utdata:

    comment_date        first_name  markup
2017-07-07 14:30:51.117 Bob         <title>Bob's Comment</title>
2017-07-07 14:30:51.117 Alice       <title>Alice's Comment</title>
2017-07-07 14:30:51.117 Bob          <Note>Text of Bob's comment.</Note>
2017-07-07 14:30:51.117 Alice        <Note>Text of Alice's comment that is much longer and wi</Note>
2017-07-07 14:30:51.117 Alice        <Text>ll need to be split over multiple rows aaaaaa bbbb</Text>
2017-07-07 14:30:51.117 Alice        <Text>bb cccccc ddddddddddd eeeeeeeeeeee fffffffffffff g</Text>
2017-07-07 14:30:51.117 Alice        <Text>gggggggggggg.</Text>