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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
-- float4 check
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CREATE TABLE float4tmp (a float4);
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\copy float4tmp from 'data/float4.data'
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SET enable_seqscan=on;
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SELECT count(*) FROM float4tmp WHERE a < -179.0;
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count
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-------
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244
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(1 row)
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SELECT count(*) FROM float4tmp WHERE a <= -179.0;
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count
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-------
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245
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(1 row)
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SELECT count(*) FROM float4tmp WHERE a = -179.0;
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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 float4tmp WHERE a >= -179.0;
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count
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-------
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303
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(1 row)
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SELECT count(*) FROM float4tmp WHERE a > -179.0;
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count
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-------
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302
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(1 row)
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SELECT a, a <-> '-179.0' FROM float4tmp ORDER BY a <-> '-179.0' LIMIT 3;
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a | ?column?
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----------+----------
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-179 | 0
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-189.024 | 10.0239
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-158.177 | 20.8226
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(3 rows)
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CREATE INDEX float4idx ON float4tmp USING gist ( a );
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SET enable_seqscan=off;
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SELECT count(*) FROM float4tmp WHERE a < -179.0::float4;
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count
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-------
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244
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(1 row)
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SELECT count(*) FROM float4tmp WHERE a <= -179.0::float4;
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count
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-------
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245
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(1 row)
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SELECT count(*) FROM float4tmp WHERE a = -179.0::float4;
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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 float4tmp WHERE a >= -179.0::float4;
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count
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-------
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303
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(1 row)
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SELECT count(*) FROM float4tmp WHERE a > -179.0::float4;
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count
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-------
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302
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(1 row)
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EXPLAIN (COSTS OFF)
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SELECT a, a <-> '-179.0' FROM float4tmp ORDER BY a <-> '-179.0' LIMIT 3;
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QUERY PLAN
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-----------------------------------------------
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Limit
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-> Index Scan using float4idx on float4tmp
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Order By: (a <-> (-179)::real)
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(3 rows)
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SELECT a, a <-> '-179.0' FROM float4tmp ORDER BY a <-> '-179.0' LIMIT 3;
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a | ?column?
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----------+----------
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-179 | 0
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-189.024 | 10.0239
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-158.177 | 20.8226
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(3 rows)
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