Re: Real life SQL Brain teaser

Choosing good example data is an art.

One thing that is confusing here is that it's not clear whether the
"Customer" and "combination" values are in the same space.

Let's say instead you have the following data:

Customer, Type, Code
100, T1, C1
100, T1, C2
200, T2, C3
200, T2, C4
300, T5, C1
400, T1, C1
400, T1, C2

Are the combinations still 1, 2, and 3? Or do they become 100, 200, and 300?

If the latter, does it matter whether you get 200, 300, 400 instead?

John Y.


On Wed, Nov 18, 2020 at 1:07 PM Dave <dfx1@xxxxxxxxxxxxxx> wrote:

In my table below there are 4 customers but only 3 distinct combinations of
Type and Code.

Customer Type Code
1 T1 C1
1 T1 C2
2 T2 C3
2 T2 C4
3 T5 C1
4 T1 C1
4 T1 C2

From this table, can I create the following table that contains each
combination of Type and Code only once ?

combination Type Code

1 T1 C1
1 T1 C2
2 T2 C3
2 T2 C4
3 T5 C1