On 04/08/2014 02:51 PM, CS_DBA wrote:
> Hi All
>
> we have a table like so:
>
>
> customer (
> cust_id integer not null primary key,
> cust_group_id integer not null,
> group_account_id integer not null,
> cust_name varchar not null,
>
> ...
> )
>
> we want to force the cust_group_id to be unique across all
> group_account_id's but not necessarily across the entire table
>
> I assume the best approach would be a check constraint yes? Will this
> be excessively poor per performance if the table gets big?
>
> Thoughts?
>
> Thanks in advance
>
>
>
>
>
A unique index on cust_group_id and group_account_id doesn't do it for you?