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e09b48316c
inet, cidr, and timetz indexes still cannot support index-only scans, because they don't store the original unmodified value in the index, but a derived approximate value.
92 lines
2.5 KiB
Plaintext
92 lines
2.5 KiB
Plaintext
-- timestamp check
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CREATE TABLE timestamptmp (a timestamp);
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\copy timestamptmp from 'data/timestamp.data'
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SET enable_seqscan=on;
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SELECT count(*) FROM timestamptmp WHERE a < '2004-10-26 08:55:08';
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count
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-------
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278
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(1 row)
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SELECT count(*) FROM timestamptmp WHERE a <= '2004-10-26 08:55:08';
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count
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-------
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279
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(1 row)
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SELECT count(*) FROM timestamptmp WHERE a = '2004-10-26 08:55:08';
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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 timestamptmp WHERE a >= '2004-10-26 08:55:08';
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count
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-------
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290
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(1 row)
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SELECT count(*) FROM timestamptmp WHERE a > '2004-10-26 08:55:08';
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count
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-------
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289
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(1 row)
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SELECT a, a <-> '2004-10-26 08:55:08' FROM timestamptmp ORDER BY a <-> '2004-10-26 08:55:08' LIMIT 3;
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a | ?column?
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--------------------------+------------------------------------
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Tue Oct 26 08:55:08 2004 | @ 0
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Sun Oct 31 06:35:03 2004 | @ 4 days 21 hours 39 mins 55 secs
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Mon Nov 29 20:12:43 2004 | @ 34 days 11 hours 17 mins 35 secs
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(3 rows)
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CREATE INDEX timestampidx ON timestamptmp USING gist ( a );
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SET enable_seqscan=off;
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SELECT count(*) FROM timestamptmp WHERE a < '2004-10-26 08:55:08'::timestamp;
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count
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-------
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278
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(1 row)
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SELECT count(*) FROM timestamptmp WHERE a <= '2004-10-26 08:55:08'::timestamp;
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count
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-------
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279
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(1 row)
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SELECT count(*) FROM timestamptmp WHERE a = '2004-10-26 08:55:08'::timestamp;
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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 timestamptmp WHERE a >= '2004-10-26 08:55:08'::timestamp;
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count
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-------
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290
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(1 row)
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SELECT count(*) FROM timestamptmp WHERE a > '2004-10-26 08:55:08'::timestamp;
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count
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-------
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289
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(1 row)
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EXPLAIN (COSTS OFF)
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SELECT a, a <-> '2004-10-26 08:55:08' FROM timestamptmp ORDER BY a <-> '2004-10-26 08:55:08' 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 timestampidx on timestamptmp
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Order By: (a <-> 'Tue Oct 26 08:55:08 2004'::timestamp without time zone)
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(3 rows)
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SELECT a, a <-> '2004-10-26 08:55:08' FROM timestamptmp ORDER BY a <-> '2004-10-26 08:55:08' LIMIT 3;
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a | ?column?
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--------------------------+------------------------------------
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Tue Oct 26 08:55:08 2004 | @ 0
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Sun Oct 31 06:35:03 2004 | @ 4 days 21 hours 39 mins 55 secs
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Mon Nov 29 20:12:43 2004 | @ 34 days 11 hours 17 mins 35 secs
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(3 rows)
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