SQL: Replace Part Of A Column On Multiple Rows Based On Second Table

I have a table (pages) that holds properties for web pages, including a column for the page content itself, an NVARCHAR(MAX) column. Within that column, I need to find and replace

Solution 1:

Here's a single-statement, non-cursor method which makes use of a CTE:

WITH CTE(iteration, page_id, content) AS (
    SELECT
        0,
        P.page_id,
        REPLACE(P.content, M1.old_value, M1.new_value)
    FROM
        Pages P
    INNER JOIN Moving M1 ON
        P.content LIKE '%' + M1.old_value + '%'
    WHERE
        NOT EXISTS (SELECT * FROM Moving M2 WHERE P.content LIKE '%' + M2.old_value + '%' AND M2.moving_id < M1.moving_id)
    UNION ALL
    SELECT
        CTE.iteration + 1,
        CTE.page_id,
        REPLACE(CTE.content, M3.old_value, M3.new_value)
    FROM
        CTE
    INNER JOIN Moving M3 ON
        CTE.content LIKE '%' + M3.old_value + '%'
    WHERE
        NOT EXISTS (SELECT * FROM Moving M4 WHERE CTE.content LIKE '%' + M4.old_value + '%' AND M4.moving_id < M3.moving_id)
)
UPDATE P2
SET
    content = CTE1.content
FROM
    Pages P2
INNER JOIN CTE CTE1 ON
    CTE1.page_id = P2.page_id AND
    NOT EXISTS (SELECT * FROM CTE CTE2 WHERE page_id = P2.page_id AND CTE2.iteration > CTE1.iteration)

Solution 2:

Try this

DECLARE @OldV NVARCHAR(32)    -- Adjust for your field sizes in MOVING
DECLARE @NEWV NVARCHAR(32)

DECLARE db_cursor CURSOR FOR  
SELECT *
FROM Moving

OPEN db_cursor   
FETCH NEXT FROM db_cursor INTO @OldV,@newV

WHILE @@FETCH_STATUS = 0   
BEGIN   
    UPDATE Pages SET content=REPLACE(content,@oldV,@NewV)
      WHERE content LIKE '%'+@OldV+'%'
       FETCH NEXT FROM db_cursor INTO @oldV,@NewV
END   

CLOSE db_cursor   
DEALLOCATE db_cursor

Although I generally don't like cursors, this should do the trick for you