1set enable_seqscan=off;
2CREATE TABLE test_name (
3	i name
4);
5INSERT INTO test_name VALUES ('a'),('ab'),('abc'),('abb'),('axy'),('xyz');
6CREATE INDEX idx_name ON test_name USING gin (i);
7SELECT * FROM test_name WHERE i<'abc' ORDER BY i;
8  i
9-----
10 a
11 ab
12 abb
13(3 rows)
14
15SELECT * FROM test_name WHERE i<='abc' ORDER BY i;
16  i
17-----
18 a
19 ab
20 abb
21 abc
22(4 rows)
23
24SELECT * FROM test_name WHERE i='abc' ORDER BY i;
25  i
26-----
27 abc
28(1 row)
29
30SELECT * FROM test_name WHERE i>='abc' ORDER BY i;
31  i
32-----
33 abc
34 axy
35 xyz
36(3 rows)
37
38SELECT * FROM test_name WHERE i>'abc' ORDER BY i;
39  i
40-----
41 axy
42 xyz
43(2 rows)
44
45EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i<'abc' ORDER BY i;
46                 QUERY PLAN
47---------------------------------------------
48 Sort
49   Sort Key: i
50   ->  Bitmap Heap Scan on test_name
51         Recheck Cond: (i < 'abc'::name)
52         ->  Bitmap Index Scan on idx_name
53               Index Cond: (i < 'abc'::name)
54(6 rows)
55
56EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i<='abc' ORDER BY i;
57                  QUERY PLAN
58----------------------------------------------
59 Sort
60   Sort Key: i
61   ->  Bitmap Heap Scan on test_name
62         Recheck Cond: (i <= 'abc'::name)
63         ->  Bitmap Index Scan on idx_name
64               Index Cond: (i <= 'abc'::name)
65(6 rows)
66
67EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i='abc' ORDER BY i;
68              QUERY PLAN
69---------------------------------------
70 Bitmap Heap Scan on test_name
71   Recheck Cond: (i = 'abc'::name)
72   ->  Bitmap Index Scan on idx_name
73         Index Cond: (i = 'abc'::name)
74(4 rows)
75
76EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i>='abc' ORDER BY i;
77                  QUERY PLAN
78----------------------------------------------
79 Sort
80   Sort Key: i
81   ->  Bitmap Heap Scan on test_name
82         Recheck Cond: (i >= 'abc'::name)
83         ->  Bitmap Index Scan on idx_name
84               Index Cond: (i >= 'abc'::name)
85(6 rows)
86
87EXPLAIN (COSTS OFF) SELECT * FROM test_name WHERE i>'abc' ORDER BY i;
88                 QUERY PLAN
89---------------------------------------------
90 Sort
91   Sort Key: i
92   ->  Bitmap Heap Scan on test_name
93         Recheck Cond: (i > 'abc'::name)
94         ->  Bitmap Index Scan on idx_name
95               Index Cond: (i > 'abc'::name)
96(6 rows)
97
98