How to say one of a group of columns is required?

Hi,

I have a table with three columns - one or more of which is required.

E.G.

MY_KEY
MY_LOOKUP1
MY_LOOKUP2
MY_LOOKUP3

where at least one of the MY_LOOKUPs is required.

Is there a check constraint for this?

I'm using Designer/2000 rel 2.1.1 onto an Oracle 7.3.4 database (later moving to 8.1.6 database).

Andy

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Andy Hardy. PGP ID: 0xA62A4849
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