Re: Best way to get all different values in a column

On Fri, Oct 14, 2005 at 06:02:56PM +0200, ext-christian(dot)roche(at)nokia(dot)com wrote:
> Does anyone here know what is the most efficient way to list all
> different values of a given column with low cardinality ? For instance
> I have a table with columns DAY, NAME, ID, etc. The table is updated
> about each week with thousands of records with the same (current) date.
> Now I would like to list all values for DAY, only if possible without
> scanning all the table each time I submit the request.
> I can think of:
> ...
> Solution 6: Store the values in a separate table, recreated each time
> TABLE is updated.

I've found a variant on 6 to work well for this problem domain.

Why not insert into the separate table, when you insert into the table?
Either as a trigger, or in your application.

Cheers,
mark

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