Re: WIP: BRIN multi-range indexes

On Mon, Sep 28, 2020 at 10:12 PM Tomas Vondra
<tomas(dot)vondra(at)2ndquadrant(dot)com> wrote:

> Is it actually all that different from the existing BRIN indexes?
> Consider this example:
>
> create table x (a text, b text, c text);
>
> create index on x using brin (a,b,c);
>
> create or replace function random_str(p_len int) returns text as $$
> select string_agg(x, '') from (select chr(1 + (254 * random())::int ) as x from generate_series(1,$1)) foo;
> $$ language sql;
>
> test=# insert into x select random_str(1000), random_str(1000), random_str(1000);
> ERROR: index row size 9056 exceeds maximum 8152 for index "x_a_b_c_idx"

Hmm, okay. As for which comes first, insert or index creation, I'm
baffled, too. I also would expect the example above would take up a
bit over 6000 bytes, but not 9000.

--
John Naylor https://www.2ndQuadrant.com/
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