Re: Help: Need Random sample of 3K from a query returning 100K

In article <8dfg7o$1tr$1_at_nnrp1.deja.com>,   George <ghharrac_at_neodata.com> wrote:
> Can oracle return a Random Sampling (Nthing) of 3K records from 10K
> records/tuples that my select statement returns?
>
> Oracle 8 has a feature to do this but the size of the return
> set is also random, which I cannot use.
>
> The returned data does not have to be statistically sampled.
>
> George
>
> Please directly email me.
>

If the first X number of rows that meet your where clause conditions would do, then you might be able to use the rownum psuedo column as in:

select * from table_x where rownum < Y

where Y is some percentage of the number of rows. You can use the average row length and number of rows in all_tables to calculate Y for limiting it to fitting in Z bytes providing statistics exist on the target table.

>

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