I want to create a unique field on 2 columns named (customer_id ,
but the problem I have in having this is in my customer table
customer_id field is unique and can have more than 4-5 values for
is_default field. hence if I want to create a unique key composed of
the above 2 keys then it would not happen as my same customer_id have
4-5 is_default values and I want them to be unique for each combination
in the table.....
so any suggestion with this are highly appreciated ....