SQL Server : get size of longest value in column and include column name in that total

Question

I have the following query that returns the number of the longest word it finds within that column:

SELECT 
    MAX(LEN(id)) AS id, 
    MAX(LEN(linkToTbl2)) AS linkToTbl2, 
    MAX(LEN(description)) AS description, 
    MAX(LEN(number)) AS number, 
    MAX(LEN(line)) AS line, 
    MAX(LEN(network)) AS network, 
    MAX(LEN(type)) AS type, 
    MAX(LEN(IPhase)) AS IPhase, 
    MAX(LEN(environment)) AS environment, 
    MAX(LEN(sType)) AS sType, 
    MAX(LEN(bDescription)) AS bDescription
FROM 
    bLine

However, if said column is smaller than the heading for that column then it doesn't take that into account when calculating the largest value.

Example (what I am looking to do):

|id | linkToTbl2 | description             |
+---+------------+-------------------------+
|14 |hi          |This is just a demo.     |
|16 |baa         |Another description here.|

Which would look like this in an example query:

|id |linkToTbl2 |description |
+---+-----------+------------+
|2  |10         |25          |

Now this is what it currently looks like in my SSRS report:

|id |lin|description              |
|   |kTo|                         |
|   |tbl|                         |
|   |2  |                         |
|---|---|-------------------------|
|14 |hi |This is just a demo.     |
|16 |baa|Another description here.|

and this would look like this in the query:

|id |linkToTbl2 |description |
|---|-----------|------------|
|2  |3          |25          |

Notice how the linkToTbl2 field is compressed since the longest value in that column is 3 (baa). linkToTbl2 would be 10 (linkToTbl2) so it should be 10 and not 3.

How can I add the columns name into the query to count that as well?

Answer 1

You can use UNPIVOT and PIVOT

DECLARE @MyTable TABLE (id INT,  linkToTbl2 VARCHAR(100),  description  VARCHAR(100))
INSERT INTO @MyTable VALUES
(14,'hi','This is just a demo.'),
(16,'baa','Another description here.')


SELECT * FROM 
    ( SELECT 
        Col,  
        MAX(CASE WHEN LEN(Val) > LEN(Col) THEN LEN(Val) ELSE LEN(Col) END) LEN_OF_COL  
      FROM 
        ( SELECT 
                CONVERT(VARCHAR(MAX),[Id]) [Id], 
                CONVERT(VARCHAR(MAX),[linkToTbl2]) [linkToTbl2], 
                CONVERT(VARCHAR(MAX),[description]) [description] 
            FROM @MyTable ) SRC
        UNPIVOT (Val FOR Col IN( [Id], [linkToTbl2], [description] ) ) UNPVT
    GROUP BY Col ) T 
PIVOT( MAX(LEN_OF_COL) FOR Col IN ( [Id], [linkToTbl2], [description] ) ) PVT

Result:

Id          linkToTbl2  description
----------- ----------- -----------
2           10          25