Select with transposition and join

Question

Hi Guys!
I'm using Oracle 9i and I'm facing the following problem:
My table looks like this:
Stripe
Unit
Value
1
1
a1
1
2
a2
1
3
a3
2
1
b1
2
2
b2
2
3
b3
2
4
b4
4
1
c1
4
2
c2
4
3
c3
4
4
c4
4
5
c5
My result should look like this:
Unit
Stripe1 Value
Stripe2 Value
Stripe3 Value
Stripe4 Value
1
a1
b1
c1
2
a2
b2
c2
3
a3
b3
c3
4
b4
c4
5
c5
I tried it with one select for each stripe and full joins, but in this example I would only see the first 3 units....
Any ideas?

Answer 1

Another way, but only if your on database version 11gR1 and onwards, is to use the PIVOT operator:
SQL> -- generating sample date:
SQL> with t as (
  2  select 1 stripe, 1 unit, 'a1' value from dual union
  3  select 1, 2, 'a2' from dual union
  4  select 1, 3, 'a3' from dual union
  5  select 2, 1, 'b1' from dual union
  6  select 2, 2, 'b2' from dual union
  7  select 2, 3, 'b3' from dual union
  8  select 2, 4, 'b4' from dual union
  9  select 4, 1, 'c1' from dual union
10  select 4, 2, 'c2' from dual union
11  select 4, 3, 'c3' from dual union
12  select 4, 4, 'c4' from dual union
13  select 4, 5, 'c5' from dual
14  )
15  --
16  -- actual query:
17  --
18  select *
19  from ( select unit
20         ,      stripe
21         ,      value
22         from   t
23       )
24  pivot (max(value) for (stripe) in ( 1 as stripe1value
25                                    , 2 as stripe2value
26                                    , 3 as stripe3value
27                                    , 4 as stripe4value
28                                    )
29        )
30  order by unit;
      UNIT ST ST ST ST
         1 a1 b1    c1
         2 a2 b2    c2
         3 a3 b3    c3
         4    b4    c4
         5          c5
5 rows selected.
ORACLE-BASE - PIVOT and UNPIVOT Operators in Oracle Database 11g Release 1