Question

I have some data in my table as follows:

 ID     Name
  2    219SUN_BV_Secure_Gateway.pdf
  3    197FDD_BV_Secure_Gateway.pdf
  5    225RQB_BV_Secure_Gateway.pdf
  6    A_00025_Q1_2012.pdf         
  7    A_00025_Q2_2012.pdf         
  8    A_00025_Q3_2011.pdf         
  9    C_00025_Q3_2011_PostLLC.pdf
 10    B_00025_Q3_2011.pdf        

I want to fetch the data as per the following requirement:

• in first column, I want data whose name starts with A
• in Second column, I want data whose name starts with B
• in Third column, I want data whose name starts with C

I used this query:

SELECT 
    CASE 
        WHEN DocumentFile LIKE 'A%' THEN DocumentFile 
    END as DocFile_A,
    CASE
        WHEN DocumentFile LIKE 'B%' THEN DocumentFile 
    END as DocFile_B,
    CASE 
        WHEN DocumentFile LIKE 'C%' THEN DocumentFile 
    END as DocFile_C 
FROM 
    RFP_DocumentVault 

This returns me the following results:

DocFile_A              DocFile_B          DocFile_C
 NULL          NULL             NULL
 NULL          NULL             NULL
 NULL          NULL             NULL
 A_00025_Q1_2012.pdf   NULL             NULL
 A_00025_Q2_2012.pdf   NULL             NULL
 A_00025_Q3_2011.pdf   NULL             NULL
 NULL          NULL           C_00025_Q3_2011_Post Partners II, LLC.pdf
 NULL          B_00025_Q3_2011.pdf        NULL

But I want results as follows:

 DocFile_A            DocFile_B                 DocFile_C
 A_00025_Q1_2012.pdf  B_00025_Q3_2011.pdf     C_00025_Q3_2011_Post Partners II, LLC.pdf
 A_00025_Q2_2012.pdf  NULL                      NULL
 A_00025_Q3_2011.pdf  NULL                      NULL

Any idea how I can do this?

Answer 1

Agree with @GolezTrol, this is something that should perhaps be solved at the presentation level. But if you are absolutely sure you need to do that in SQL, here’s an alternative to their solution:

WITH ranked AS (
  SELECT
    DocumentFile,
    grp = 'DocFile_' + LEFT(DocumentFile, 1),
    rnk = ROW_NUMBER() OVER (
      PARTITION BY LEFT(DocumentFile, 1)
      ORDER BY DocumentFile
    )
  FROM RFP_DocumentVault
)
SELECT *
FROM ranked
PIVOT (
  MAX(DocumentFile) FOR grp IN (DocFile_A, DocFile_B, DocFile_C)
) p
;

There’s a live demo at SQL Fiddle too.