>I don´t see the need to create a concatenated index. Why do you want to create such an index? If you are going the query the table it will be on either one of the fk´s. Having an index for each of them is enough. There is no need to join them in a string.
I understand that the concatenated index would not be used for PK or FK purposes, but to avoid duplicate records (by defining the index as "candidate").
I have often used concatenated indices in this way, to ensure uniqueness for a combination of two or more fields.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
