HELP ! is it transpose, pivot, decode, case or connect by- haven't a clue!

Question

I'm almost embarrassed about asking this but my sql skills just haven't kept up since 8i !!
I know i could write a procedure and put the data into a temp table , but i really should get with the program and learn some new functions !!
using select wo_num, g_start,g_end from batch
I have a row returned from a table like so
WO_NUM G_START G_END
1000000 100 105
Using a select statement I would like to turn it into
WO_NUM G
1000000 100
1000000 101
1000000 102
1000000 103
1000000 104
1000000 105

Answer 1

Hi,
You're asking about a counter table, that is, a result set (that you can use like a table) that has all possible values in a range: in this case, all the integers between g_start and g_end.
In Oracle 9 (and up) you can generate such a counter table using CONNECT BY.
The query below does what you want for all rows in table_x:
WITH     cntr     AS
     SELECT     LEVEL - 1     AS n
     FROM     dual
     CONNECT BY     LEVEL <= 1 + (
                                     SELECT  MAX (g_end - g_start)
                              FROM    table_x
SELECT    x.wo_num
,       g_start + c.n     AS g
FROM       table_x     x
JOIN       cntr          c     ON  x.g_end >= x.g_start + c.n
ORDER BY  x.wo_num
,            g;But you don't want to do this for every row in table_x: you want to do it for every row in the result set of your original query. (It doesn't matter if there's only one row or not.)
So add your original query as another sub-query, and use that instead of table_x:
WITH       original_results  AS
     SELECT     wo_num
     ,     g_start
     ,     g_end
     FROM     table_x
     WHERE     column_1     < column_2
,     cntr     AS
     SELECT     LEVEL - 1     AS n
     FROM     dual
     CONNECT BY     LEVEL <= 1 + (
                                     SELECT  MAX (g_end - g_start)
                              FROM    original_results
SELECT    x.wo_num
,       g_start + c.n     AS g
FROM       original_results     x
JOIN       cntr               c     ON  x.g_end >= x.g_start + c.n
ORDER BY  x.wo_num
,            g;The original query in this example is pretty simple, but you can use any query, involving joins and sub-queries.