110 lines
2.7 KiB
Plaintext
110 lines
2.7 KiB
Plaintext
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set enable_seqscan=off;
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CREATE TABLE test_bpchar (
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i char(10)
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);
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INSERT INTO test_bpchar VALUES ('a'),('ab'),('abc'),('abc '),('abb'),('axy'),('xyz'),('xyz ');
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CREATE INDEX idx_bpchar ON test_bpchar USING gin (i);
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SELECT * FROM test_bpchar WHERE i<'abc' ORDER BY i;
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i
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------------
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a
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ab
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abb
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(3 rows)
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SELECT * FROM test_bpchar WHERE i<='abc' ORDER BY i;
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i
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------------
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a
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ab
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abb
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abc
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abc
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(5 rows)
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SELECT * FROM test_bpchar WHERE i='abc' ORDER BY i;
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i
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------------
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abc
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abc
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(2 rows)
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SELECT * FROM test_bpchar WHERE i='abc ' ORDER BY i;
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i
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------------
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abc
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abc
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(2 rows)
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SELECT * FROM test_bpchar WHERE i>='abc' ORDER BY i;
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i
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------------
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abc
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abc
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axy
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xyz
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xyz
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(5 rows)
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SELECT * FROM test_bpchar WHERE i>'abc' ORDER BY i;
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i
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------------
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axy
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xyz
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xyz
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(3 rows)
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EXPLAIN (COSTS OFF) SELECT * FROM test_bpchar WHERE i<'abc' ORDER BY i;
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QUERY PLAN
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-----------------------------------------------
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Sort
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Sort Key: i
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-> Bitmap Heap Scan on test_bpchar
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Recheck Cond: (i < 'abc'::bpchar)
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-> Bitmap Index Scan on idx_bpchar
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Index Cond: (i < 'abc'::bpchar)
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(6 rows)
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EXPLAIN (COSTS OFF) SELECT * FROM test_bpchar WHERE i<='abc' ORDER BY i;
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QUERY PLAN
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------------------------------------------------
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Sort
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Sort Key: i
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-> Bitmap Heap Scan on test_bpchar
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Recheck Cond: (i <= 'abc'::bpchar)
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-> Bitmap Index Scan on idx_bpchar
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Index Cond: (i <= 'abc'::bpchar)
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(6 rows)
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EXPLAIN (COSTS OFF) SELECT * FROM test_bpchar WHERE i='abc' ORDER BY i;
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QUERY PLAN
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-----------------------------------------
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Bitmap Heap Scan on test_bpchar
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Recheck Cond: (i = 'abc'::bpchar)
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-> Bitmap Index Scan on idx_bpchar
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Index Cond: (i = 'abc'::bpchar)
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(4 rows)
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EXPLAIN (COSTS OFF) SELECT * FROM test_bpchar WHERE i>='abc' ORDER BY i;
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QUERY PLAN
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------------------------------------------------
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Sort
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Sort Key: i
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-> Bitmap Heap Scan on test_bpchar
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Recheck Cond: (i >= 'abc'::bpchar)
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-> Bitmap Index Scan on idx_bpchar
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Index Cond: (i >= 'abc'::bpchar)
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(6 rows)
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EXPLAIN (COSTS OFF) SELECT * FROM test_bpchar WHERE i>'abc' ORDER BY i;
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QUERY PLAN
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-----------------------------------------------
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Sort
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Sort Key: i
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-> Bitmap Heap Scan on test_bpchar
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Recheck Cond: (i > 'abc'::bpchar)
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-> Bitmap Index Scan on idx_bpchar
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Index Cond: (i > 'abc'::bpchar)
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(6 rows)
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