Column to Row Display

Question

Hi,
I have 252 column table data, where in I need to display some of those columns values as rows in my report.
col1 col2 col3 col4 .... col252
i want to display this as
row1
row2
row3
row252.
I am unable to use Pivot as I am using Oracle 10g. Pls suggest a solution on this?

Answer 1

Hi,
Always post your Oracle version. Don't just add an easy-to-miss tag like "10G" to your message; say something clear, like "I'm using Oracle 10.2.0.4.0".
This is called Unpivot . One way to do it is to cross-join your table to a Counter Table , any table (or sub-query, as in the example below) that has as many rows as you need in your output.
To unpivot all 252 columns:
WITH     cntr     AS
     SELECT     LEVEL     AS n
     FROM     dual
     CONNECT BY     LEVEL     <= 252
SELECT     c.n
,     CASE
         WHEN  c.n <= 100
         THEN  CASE c.n
               WHEN   1  THEN     x.col_1
               WHEN   2  THEN  x.col_2
               WHEN 100  THEN  x.col_100
            END
         WHEN  c.n <= 200
         THEN  CASE c.n
               WHEN 101  THEN     x.col_101
               WHEN 102  THEN  x.col_102
               WHEN 200  THEN  x.col_200
            END
         WHEN  c.n <= 300
         THEN  CASE c.n
               WHEN 201  THEN     x.col_201
               WHEN 202  THEN  x.col_202
               WHEN 252  THEN  x.col_252
            END
     END     AS data_col
FROM          cntr     c
CROSS JOIN     table_x     x
;The nested CASE expressions are necessary because you can't have more than 127 WHEN-THEN pairs in a single CASE expression.
If you're choosing 60 columns out of the 252 to unoivot, then you only need one CASE expression.