83 lines
1.6 KiB
Plaintext
83 lines
1.6 KiB
Plaintext
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-- char check
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CREATE TABLE chartmp (a char(32));
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\copy chartmp from 'data/char.data'
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SET enable_seqscan=on;
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SELECT count(*) FROM chartmp WHERE a < '31b0'::char(32);
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count
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-------
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773
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(1 row)
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SELECT count(*) FROM chartmp WHERE a <= '31b0'::char(32);
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count
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-------
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774
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(1 row)
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SELECT count(*) FROM chartmp WHERE a = '31b0'::char(32);
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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 chartmp WHERE a >= '31b0'::char(32);
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count
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-------
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215
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(1 row)
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SELECT count(*) FROM chartmp WHERE a > '31b0'::char(32);
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count
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-------
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214
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(1 row)
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CREATE INDEX charidx ON chartmp USING GIST ( a );
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SET enable_seqscan=off;
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SELECT count(*) FROM chartmp WHERE a < '31b0'::char(32);
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count
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-------
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773
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(1 row)
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SELECT count(*) FROM chartmp WHERE a <= '31b0'::char(32);
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count
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-------
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774
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(1 row)
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SELECT count(*) FROM chartmp WHERE a = '31b0'::char(32);
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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 chartmp WHERE a >= '31b0'::char(32);
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count
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-------
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215
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(1 row)
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SELECT count(*) FROM chartmp WHERE a > '31b0'::char(32);
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count
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-------
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214
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(1 row)
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-- Test index-only scans
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SET enable_bitmapscan=off;
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EXPLAIN (COSTS OFF)
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SELECT * FROM chartmp WHERE a BETWEEN '31a' AND '31c';
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QUERY PLAN
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---------------------------------------------------------------
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Index Only Scan using charidx on chartmp
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Index Cond: ((a >= '31a'::bpchar) AND (a <= '31c'::bpchar))
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(2 rows)
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SELECT * FROM chartmp WHERE a BETWEEN '31a' AND '31c';
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a
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----------------------------------
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31b0
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(1 row)
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