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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
2.1 KiB
Plaintext
99 lines
2.1 KiB
Plaintext
-- time check
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CREATE TABLE timetmp (a time);
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\copy timetmp from 'data/time.data'
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SET enable_seqscan=on;
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SELECT count(*) FROM timetmp WHERE a < '10:57:11';
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count
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-------
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251
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(1 row)
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SELECT count(*) FROM timetmp WHERE a <= '10:57:11';
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count
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-------
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252
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(1 row)
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SELECT count(*) FROM timetmp WHERE a = '10:57:11';
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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 timetmp WHERE a >= '10:57:11';
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count
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-------
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293
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(1 row)
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SELECT count(*) FROM timetmp WHERE a > '10:57:11';
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count
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-------
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292
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(1 row)
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SELECT a, a <-> '10:57:11' FROM timetmp ORDER BY a <-> '10:57:11' LIMIT 3;
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a | ?column?
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----------+-----------------
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10:57:11 | @ 0
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10:57:10 | @ 1 sec
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10:55:32 | @ 1 min 39 secs
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(3 rows)
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SET client_min_messages = DEBUG1;
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CREATE INDEX timeidx ON timetmp USING gist ( a );
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DEBUG: building index "timeidx" on table "timetmp" serially
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DEBUG: using sorted GiST build
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CREATE INDEX timeidx_b ON timetmp USING gist ( a ) WITH (buffering=on);
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DEBUG: building index "timeidx_b" on table "timetmp" serially
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DROP INDEX timeidx_b;
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RESET client_min_messages;
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SET enable_seqscan=off;
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SELECT count(*) FROM timetmp WHERE a < '10:57:11'::time;
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count
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-------
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251
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(1 row)
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SELECT count(*) FROM timetmp WHERE a <= '10:57:11'::time;
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count
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-------
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252
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(1 row)
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SELECT count(*) FROM timetmp WHERE a = '10:57:11'::time;
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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 timetmp WHERE a >= '10:57:11'::time;
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count
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-------
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293
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(1 row)
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SELECT count(*) FROM timetmp WHERE a > '10:57:11'::time;
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count
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-------
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292
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(1 row)
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EXPLAIN (COSTS OFF)
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SELECT a, a <-> '10:57:11' FROM timetmp ORDER BY a <-> '10:57:11' 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 timeidx on timetmp
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Order By: (a <-> '10:57:11'::time without time zone)
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(3 rows)
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SELECT a, a <-> '10:57:11' FROM timetmp ORDER BY a <-> '10:57:11' LIMIT 3;
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a | ?column?
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----------+-----------------
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10:57:11 | @ 0
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10:57:10 | @ 1 sec
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10:55:32 | @ 1 min 39 secs
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(3 rows)
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