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-- test selectivity estimator functions
create table spoint10k (star spoint);
insert into spoint10k select spoint(i, i*i) from generate_series(1, 10000) g(i);
create index on spoint10k using gist (star);
analyze spoint10k;
-- "explain analyze" wrapper that removes 'cost=...' since it varies across architectures
-- (we can't use "costs off" since that also removes the estimated row count)
create or replace function explain(query text, do_analyze text default 'true') returns setof text language plpgsql as $$
declare
line text;
begin
for line in execute format('explain (analyze %s, timing off, summary off, buffers off) %s', do_analyze, query) loop
continue when (line ~ ' +Index Searches: .*');
return next regexp_replace(line, 'cost=\S+ ', '');
end loop;
return;
end;
$$;
-- <@ operator selectivity
select explain('select * from spoint10k where star <@ scircle(spoint(1,1), 1)');
explain
-----------------------------------------------------------------------------------------------
Bitmap Heap Scan on spoint10k (rows=2298 width=16) (actual rows=3009 loops=1)
Recheck Cond: (star <@ '<(1 , 1) , 1>'::scircle)
Rows Removed by Index Recheck: 1560
Heap Blocks: exact=55
-> Bitmap Index Scan on spoint10k_star_idx (rows=2298 width=0) (actual rows=4569 loops=1)
Index Cond: (star <@ '<(1 , 1) , 1>'::scircle)
(6 rows)
select explain('select * from spoint10k where star <@ scircle(spoint(1,1), .1)');
explain
-------------------------------------------------------------------------------------------
Bitmap Heap Scan on spoint10k (rows=25 width=16) (actual rows=29 loops=1)
Recheck Cond: (star <@ '<(1 , 1) , 0.1>'::scircle)
Rows Removed by Index Recheck: 19
Heap Blocks: exact=32
-> Bitmap Index Scan on spoint10k_star_idx (rows=25 width=0) (actual rows=48 loops=1)
Index Cond: (star <@ '<(1 , 1) , 0.1>'::scircle)
(6 rows)
select explain('select * from spoint10k where star <@ scircle(spoint(1,1), .01)');
explain
---------------------------------------------------------------------------------------------
Index Scan using spoint10k_star_idx on spoint10k (rows=1 width=16) (actual rows=1 loops=1)
Index Cond: (star <@ '<(1 , 1) , 0.01>'::scircle)
(2 rows)
select explain('select * from spoint10k where scircle(spoint(1,1), 1) @> star');
explain
-----------------------------------------------------------------------------------------------
Bitmap Heap Scan on spoint10k (rows=2298 width=16) (actual rows=3009 loops=1)
Recheck Cond: ('<(1 , 1) , 1>'::scircle @> star)
Rows Removed by Index Recheck: 1560
Heap Blocks: exact=55
-> Bitmap Index Scan on spoint10k_star_idx (rows=2298 width=0) (actual rows=4569 loops=1)
Index Cond: (star <@ '<(1 , 1) , 1>'::scircle)
(6 rows)
select explain('select * from spoint10k where scircle(spoint(1,1), .1) @> star');
explain
-------------------------------------------------------------------------------------------
Bitmap Heap Scan on spoint10k (rows=25 width=16) (actual rows=29 loops=1)
Recheck Cond: ('<(1 , 1) , 0.1>'::scircle @> star)
Rows Removed by Index Recheck: 19
Heap Blocks: exact=32
-> Bitmap Index Scan on spoint10k_star_idx (rows=25 width=0) (actual rows=48 loops=1)
Index Cond: (star <@ '<(1 , 1) , 0.1>'::scircle)
(6 rows)
select explain('select * from spoint10k where scircle(spoint(1,1), .01) @> star');
explain
---------------------------------------------------------------------------------------------
Index Scan using spoint10k_star_idx on spoint10k (rows=1 width=16) (actual rows=1 loops=1)
Index Cond: (star <@ '<(1 , 1) , 0.01>'::scircle)
(2 rows)
select explain('select * from spoint10k where star !<@ scircle(spoint(1,1), 1)');
explain
------------------------------------------------------------------------
Seq Scan on spoint10k (rows=7702 width=16) (actual rows=6991 loops=1)
Filter: (star !<@ '<(1 , 1) , 1>'::scircle)
Rows Removed by Filter: 3009
(3 rows)
select explain('select * from spoint10k where star !<@ scircle(spoint(1,1), .1)');
explain
------------------------------------------------------------------------
Seq Scan on spoint10k (rows=9975 width=16) (actual rows=9971 loops=1)
Filter: (star !<@ '<(1 , 1) , 0.1>'::scircle)
Rows Removed by Filter: 29
(3 rows)
select explain('select * from spoint10k where star !<@ scircle(spoint(1,1), .01)');
explain
-------------------------------------------------------------------------
Seq Scan on spoint10k (rows=10000 width=16) (actual rows=9999 loops=1)
Filter: (star !<@ '<(1 , 1) , 0.01>'::scircle)
Rows Removed by Filter: 1
(3 rows)
select explain('select * from spoint10k where scircle(spoint(1,1), 1) !@> star');
explain
------------------------------------------------------------------------
Seq Scan on spoint10k (rows=7702 width=16) (actual rows=6991 loops=1)
Filter: ('<(1 , 1) , 1>'::scircle !@> star)
Rows Removed by Filter: 3009
(3 rows)
select explain('select * from spoint10k where scircle(spoint(1,1), .1) !@> star');
explain
------------------------------------------------------------------------
Seq Scan on spoint10k (rows=9975 width=16) (actual rows=9971 loops=1)
Filter: ('<(1 , 1) , 0.1>'::scircle !@> star)
Rows Removed by Filter: 29
(3 rows)
select explain('select * from spoint10k where scircle(spoint(1,1), .01) !@> star');
explain
-------------------------------------------------------------------------
Seq Scan on spoint10k (rows=10000 width=16) (actual rows=9999 loops=1)
Filter: ('<(1 , 1) , 0.01>'::scircle !@> star)
Rows Removed by Filter: 1
(3 rows)
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