Re: TABLESAMPLE usage

On 01/25/2016 05:09 AM, Tom Smith wrote:
> Hello:
>
> I have a big table with that is always appended with new data with a unique
> sequence id  (always incremented, or timestamp as unique index) each row.
> I'd like to sample, say 100 rows out of say 1000 rows evently across all
> the rows,
> so that it would return  rows  of1, 101, 201, 301    you get idea.
> can TABLESAMPLE    get one row for every 100 rows, based on the order
> of the rows added to table using the timestamp as already indexed/sorted
> sequence

No, TABLESAMPLE is intended to take a random sampling of the data using
various methods.

You're looking for something more like this:

    select t.*
    from generate_series(1, (select max(id) from t), 100) g
    join t on t.id = g;
--
Vik Fearing                                          +33 6 46 75 15 36
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