Re: Compression and on-disk sorting

> Actually, I suspect in most cases it won't matter; I don't think people
> make a habit of trying to sort their entire database. :) But we'd want
> to protect for the oddball cases... yech.

I can make query result sets that are far larger than the database
itself.

create table fat_table_with_few_tuples(fat_status_id serial primary key,
fat_1 text, fat_2 text);

create table thin_table_with_many_tuples(fat_status_id integer
references fat_table_with_few_tuples, thin_1 integer, thin_2 integer);

SELECT * FROM thin_table_with_many_tuples NATURAL JOIN
fat_table_with_few_tuples order by fat_1, thin_1, thin_2, fat_2;

I would be asking the folks trying to use PostgreSQL for data
warehousing what their opinion is. A few fact tables in an audit query
could easily result in a very large amount of temporary diskspace being
required.

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