Hi,

I have a problem concerning check constraints. In the following table,

SeqID | Sequence
------------------------
1 | AAGTTTCCCC
2 | CCCGTTGGCCAAAA

the column Sequence can only contain strings of the four upper case letters A, C, G and T. Is it possible to defne a check constraint on the table to enforce this? Or do I have to use a trigger?
--Thanks for your help,

Dan1