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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
1.5 KiB
Plaintext
92 lines
1.5 KiB
Plaintext
-- int4 check
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CREATE TABLE int4tmp (a int4);
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\copy int4tmp from 'data/int2.data'
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SET enable_seqscan=on;
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SELECT count(*) FROM int4tmp 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 int4tmp 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 int4tmp 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 int4tmp 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 int4tmp 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 int4tmp 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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CREATE INDEX int4idx ON int4tmp USING gist ( a );
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SET enable_seqscan=off;
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SELECT count(*) FROM int4tmp WHERE a < 237::int4;
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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 int4tmp WHERE a <= 237::int4;
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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 int4tmp WHERE a = 237::int4;
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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 int4tmp WHERE a >= 237::int4;
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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 int4tmp WHERE a > 237::int4;
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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 int4tmp 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 int4idx on int4tmp
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Order By: (a <-> 237)
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(3 rows)
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SELECT a, a <-> '237' FROM int4tmp 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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