Thank you very much for the advices. They have given to me deep insights about my problem. But I need to apologize I’ve not described the problem appropriately. I will try it again, here:

The complete table I have is like:

Fruit, colour, Id number of supermarket

I need to be able to select only the repeated fruits in two given supermarkets. So, if I have

Mellon, red, 1
Mellon, green, 2
Banana, black, 1
Orange, blue, 3

And if I want to get information about supermarket 1 and 2, the result will be

Mellon, red, 1
Mellon, green, 2

I’m using DBI module.

Thanks!