Union Query Improvement

[Ray Bannon <bannonr@xxxxxxxxxxx>]

I have a query which is running a bit slowly, and I'm wondering if anyone
has a design improvement. Basically it's a series of unions as follows:

Select ID, plan_name from table/view
Where plan_name = 'A'
And rownum = 1
UNION
Select ID, plan_name from table/view
Where plan_name = 'B'
And rownum = 1
UNION
Select ID, plan_name from table/view
Where plan_name = 'C'
And rownum = 1
UNION

Ad infinitum for about 100 iterations.

Any way to write this more efficiently?

Thanks!