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9f984ba6d2
Commit 16fa9b2b30 introduced a faster way to build GiST indexes, by
sorting all the data. This commit adds the sortsupport functions needed
to make use of that feature for btree_gist.
Author: Andrey Borodin
Discussion: https://www.postgresql.org/message-id/2F3F7265-0D22-44DB-AD71-8554C743D943@yandex-team.ru
99 lines
1.8 KiB
Plaintext
99 lines
1.8 KiB
Plaintext
-- int2 check
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CREATE TABLE int2tmp (a int2);
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\copy int2tmp from 'data/int2.data'
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SET enable_seqscan=on;
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SELECT count(*) FROM int2tmp WHERE a < 237;
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count
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-------
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297
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(1 row)
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SELECT count(*) FROM int2tmp WHERE a <= 237;
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count
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-------
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298
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(1 row)
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SELECT count(*) FROM int2tmp WHERE a = 237;
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count
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-------
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1
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(1 row)
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SELECT count(*) FROM int2tmp WHERE a >= 237;
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count
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-------
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249
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(1 row)
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SELECT count(*) FROM int2tmp WHERE a > 237;
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count
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-------
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248
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(1 row)
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SELECT a, a <-> '237' FROM int2tmp ORDER BY a <-> '237' LIMIT 3;
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a | ?column?
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-----+----------
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237 | 0
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232 | 5
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228 | 9
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(3 rows)
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SET client_min_messages = DEBUG1;
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CREATE INDEX int2idx ON int2tmp USING gist ( a );
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DEBUG: building index "int2idx" on table "int2tmp" serially
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DEBUG: using sorted GiST build
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CREATE INDEX int2idx_b ON int2tmp USING gist ( a ) WITH (buffering=on);
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DEBUG: building index "int2idx_b" on table "int2tmp" serially
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DROP INDEX int2idx_b;
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RESET client_min_messages;
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SET enable_seqscan=off;
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SELECT count(*) FROM int2tmp WHERE a < 237::int2;
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count
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-------
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297
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(1 row)
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SELECT count(*) FROM int2tmp WHERE a <= 237::int2;
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count
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-------
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298
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(1 row)
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SELECT count(*) FROM int2tmp WHERE a = 237::int2;
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count
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-------
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1
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(1 row)
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SELECT count(*) FROM int2tmp WHERE a >= 237::int2;
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count
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-------
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249
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(1 row)
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SELECT count(*) FROM int2tmp WHERE a > 237::int2;
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count
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-------
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248
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(1 row)
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EXPLAIN (COSTS OFF)
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SELECT a, a <-> '237' FROM int2tmp ORDER BY a <-> '237' LIMIT 3;
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QUERY PLAN
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------------------------------------------------
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Limit
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-> Index Only Scan using int2idx on int2tmp
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Order By: (a <-> '237'::smallint)
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(3 rows)
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SELECT a, a <-> '237' FROM int2tmp ORDER BY a <-> '237' LIMIT 3;
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a | ?column?
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-----+----------
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237 | 0
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232 | 5
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228 | 9
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(3 rows)
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