Repetitions and combinations of values

Question

I have a table (corner) with 5 fields, each field can have the value from 1 to 80.

I wonder if it is possible in SQL or only in Delphi, to catch the dukes (combinations of 2 numbers) between 1 and 80 in the fields from C1 to C5. no matter where the values are on the line.

Example: combination of 01 and 02: 20 times.

(But 01 can be on C1, C2 or C3, and 02 can be on C4 or C5. The same number cannot be repeated on the same line).

Answer 1

--aligning

select c1 c from tabela
union all
select c2 c from tabela
union all
select c3 c from tabela
union all
select c4 c from tabela
union all
select c5 c from tabela

--reading as a table

select virtual1.*
from
(
select c1 c from tabela
union all
select c2 c from tabela
union all
select c3 c from tabela
union all
select c4 c from tabela
union all
select c5 c from tabela
) virtual1 

--forcing a Cartesian

select virtual1.*,virtual2.*
from
(
select c1 c from tabela
union all
select c2 c from tabela
union all
select c3 c from tabela
union all
select c4 c from tabela
union all
select c5 c from tabela
) virtual1,
(
select c1 c from tabela
union all
select c2 c from tabela
union all
select c3 c from tabela
union all
select c4 c from tabela
union all
select c5 c from tabela
) virtual2
where virtual1.c <. virtual2.c

The basic idea is to make an "unpivot" of the table and then force a Cartesian.