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--
-- Test GiST indexes.
--
-- There are other tests to test different GiST opclasses. This is for
-- testing GiST code itself. Vacuuming in particular.
create table gist_point_tbl(id int4, p point);
create index gist_pointidx on gist_point_tbl using gist(p);
-- Insert enough data to create a tree that's a couple of levels deep.
insert into gist_point_tbl (id, p)
select g, point(g*10, g*10) from generate_series(1, 10000) g;
insert into gist_point_tbl (id, p)
select g+100000, point(g*10+1, g*10+1) from generate_series(1, 10000) g;
-- To test vacuum, delete some entries from all over the index.
delete from gist_point_tbl where id % 2 = 1;
-- And also delete some concentration of values. (GiST doesn't currently
-- attempt to delete pages even when they become empty, but if it did, this
-- would exercise it)
delete from gist_point_tbl where id < 10000;
vacuum analyze gist_point_tbl;
--
-- Test Index-only plans on GiST indexes
--
create table gist_tbl (b box, p point, c circle);
insert into gist_tbl
select box(point(0.05*i, 0.05*i), point(0.05*i, 0.05*i)),
point(0.05*i, 0.05*i),
circle(point(0.05*i, 0.05*i), 1.0)
from generate_series(0,10000) as i;
vacuum analyze gist_tbl;
set enable_seqscan=off;
set enable_bitmapscan=off;
set enable_indexonlyscan=on;
-- Test index-only scan with point opclass
create index gist_tbl_point_index on gist_tbl using gist (p);
-- check that the planner chooses an index-only scan
explain (costs off)
select p from gist_tbl where p <@ box(point(0,0), point(0.5, 0.5));
-- execute the same
select p from gist_tbl where p <@ box(point(0,0), point(0.5, 0.5));
-- Also test an index-only knn-search
explain (costs off)
select p from gist_tbl where p <@ box(point(0,0), point(0.5, 0.5))
order by p <-> point(0.201, 0.201);
select p from gist_tbl where p <@ box(point(0,0), point(0.5, 0.5))
order by p <-> point(0.201, 0.201);
-- Check commuted case as well
explain (costs off)
select p from gist_tbl where p <@ box(point(0,0), point(0.5, 0.5))
order by point(0.101, 0.101) <-> p;
select p from gist_tbl where p <@ box(point(0,0), point(0.5, 0.5))
order by point(0.101, 0.101) <-> p;
drop index gist_tbl_point_index;
-- Test index-only scan with box opclass
create index gist_tbl_box_index on gist_tbl using gist (b);
-- check that the planner chooses an index-only scan
explain (costs off)
select b from gist_tbl where b <@ box(point(5,5), point(6,6));
-- execute the same
select b from gist_tbl where b <@ box(point(5,5), point(6,6));
drop index gist_tbl_box_index;
-- Test that an index-only scan is not chosen, when the query involves the
-- circle column (the circle opclass does not support index-only scans).
create index gist_tbl_multi_index on gist_tbl using gist (p, c);
explain (costs off)
select p, c from gist_tbl
where p <@ box(point(5,5), point(6, 6));
-- execute the same
select b, p from gist_tbl
where b <@ box(point(4.5, 4.5), point(5.5, 5.5))
and p <@ box(point(5,5), point(6, 6));
drop index gist_tbl_multi_index;
-- Clean up
reset enable_seqscan;
reset enable_bitmapscan;
reset enable_indexonlyscan;
drop table gist_tbl;
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