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8436489c81
This extends GiST's support for nearest-neighbor searches to many of the standard data types. Teodor Sigaev
92 lines
1.7 KiB
Plaintext
92 lines
1.7 KiB
Plaintext
-- date check
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CREATE TABLE datetmp (a date);
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\copy datetmp from 'data/date.data'
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SET enable_seqscan=on;
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SELECT count(*) FROM datetmp WHERE a < '2001-02-13';
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count
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-------
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230
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(1 row)
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SELECT count(*) FROM datetmp WHERE a <= '2001-02-13';
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count
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-------
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231
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(1 row)
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SELECT count(*) FROM datetmp WHERE a = '2001-02-13';
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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 datetmp WHERE a >= '2001-02-13';
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count
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-------
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314
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(1 row)
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SELECT count(*) FROM datetmp WHERE a > '2001-02-13';
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count
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-------
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313
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(1 row)
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SELECT a, a <-> '2001-02-13' FROM datetmp ORDER BY a <-> '2001-02-13' LIMIT 3;
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a | ?column?
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------------+----------
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02-13-2001 | 0
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02-11-2001 | 2
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03-24-2001 | 39
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(3 rows)
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CREATE INDEX dateidx ON datetmp USING gist ( a );
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SET enable_seqscan=off;
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SELECT count(*) FROM datetmp WHERE a < '2001-02-13'::date;
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count
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-------
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230
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(1 row)
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SELECT count(*) FROM datetmp WHERE a <= '2001-02-13'::date;
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count
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-------
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231
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(1 row)
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SELECT count(*) FROM datetmp WHERE a = '2001-02-13'::date;
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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 datetmp WHERE a >= '2001-02-13'::date;
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count
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-------
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314
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(1 row)
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SELECT count(*) FROM datetmp WHERE a > '2001-02-13'::date;
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count
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-------
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313
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(1 row)
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EXPLAIN (COSTS OFF)
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SELECT a, a <-> '2001-02-13' FROM datetmp ORDER BY a <-> '2001-02-13' LIMIT 3;
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QUERY PLAN
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----------------------------------------------
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Limit
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-> Index Scan using dateidx on datetmp
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Order By: (a <-> '02-13-2001'::date)
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(3 rows)
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SELECT a, a <-> '2001-02-13' FROM datetmp ORDER BY a <-> '2001-02-13' LIMIT 3;
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a | ?column?
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------------+----------
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02-13-2001 | 0
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02-11-2001 | 2
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03-24-2001 | 39
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(3 rows)
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