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Re: Union Query Improvement

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Ray Bannon wrote:
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.

I'm sure I'm missing something but wouldn't this give the same results:

select id, plan_name from table where rownum=1 and plan_name in ('A', 'B', 'C');

?

Or do the rownum's change later on?

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