1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
|
DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (d1 DECIMAL(10,2) <CUSTOM_COL_OPTIONS>,
d2 DECIMAL(60,10) <CUSTOM_COL_OPTIONS>,
n1 NUMERIC <CUSTOM_COL_OPTIONS>,
n2 NUMERIC(65,4) <CUSTOM_COL_OPTIONS>,
<CUSTOM_INDEX> d1 (d1)
) ENGINE=<STORAGE_ENGINE> <CUSTOM_TABLE_OPTIONS>;
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 1 # 1 d1 # # NULL NULL # #
INSERT INTO t1 (d1,d2,n1,n2) VALUES
(10.22,60.12345,123456,14.3456),
(10.0,60.12345,123456,14),
(11.14,15,123456,13),
(100,100,1,2),
(0,0,0,0),
(4540424564.23,3343303441.0,12,13),
(15,17,23,100000);
Warnings:
Warning 1264 Out of range value for column 'd1' at row 6
SELECT d1 FROM t1 ORDER BY d1 DESC;
d1
99999999.99
100.00
15.00
11.14
10.22
10.00
0.00
DROP TABLE t1;
CREATE TABLE t1 (d1 DECIMAL(10,2) <CUSTOM_COL_OPTIONS> PRIMARY KEY,
d2 DECIMAL(60,10) <CUSTOM_COL_OPTIONS>,
n1 NUMERIC <CUSTOM_COL_OPTIONS>,
n2 NUMERIC(65,4) <CUSTOM_COL_OPTIONS>
) ENGINE=<STORAGE_ENGINE> <CUSTOM_TABLE_OPTIONS>;
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 0 PRIMARY 1 d1 # # NULL NULL # #
INSERT INTO t1 (d1,d2,n1,n2) VALUES
(10.22,60.12345,123456,14.3456),
(10.0,60.12345,123456,14),
(11.14,15,123456,13),
(100,100,1,2),
(0,0,0,0),
(4540424564.23,3343303441.0,12,13),
(15,17,23,100000);
Warnings:
Warning 1264 Out of range value for column 'd1' at row 6
EXPLAIN SELECT d1 FROM t1 ORDER BY d1 DESC;
id select_type table type possible_keys key key_len ref rows Extra
# # # # # PRIMARY # # # #
SELECT d1 FROM t1 ORDER BY d1 DESC;
d1
99999999.99
100.00
15.00
11.14
10.22
10.00
0.00
EXPLAIN SELECT d1 FROM t1 IGNORE INDEX FOR ORDER BY (PRIMARY) ORDER BY d1 DESC;
id select_type table type possible_keys key key_len ref rows Extra
# # # # # PRIMARY # # # #
SELECT d1 FROM t1 IGNORE INDEX FOR ORDER BY (PRIMARY) ORDER BY d1 DESC;
d1
99999999.99
100.00
15.00
11.14
10.22
10.00
0.00
DROP TABLE t1;
CREATE TABLE t1 (d1 DECIMAL(10,2) <CUSTOM_COL_OPTIONS>,
d2 DECIMAL(60,10) <CUSTOM_COL_OPTIONS>,
n1 NUMERIC <CUSTOM_COL_OPTIONS>,
n2 NUMERIC(65,4) <CUSTOM_COL_OPTIONS>,
UNIQUE INDEX n1_n2 (n1,n2)
) ENGINE=<STORAGE_ENGINE> <CUSTOM_TABLE_OPTIONS>;
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 0 n1_n2 1 n1 # # NULL NULL # #
t1 0 n1_n2 2 n2 # # NULL NULL # #
INSERT INTO t1 (d1,d2,n1,n2) VALUES
(10.22,60.12345,123456,14.3456),
(10.0,60.12345,123456,14),
(11.14,15,123456,13),
(100,100,1,2),
(0,0,0,0),
(4540424564.23,3343303441.0,12,13),
(15,17,23,100000);
Warnings:
Warning 1264 Out of range value for column 'd1' at row 6
EXPLAIN SELECT DISTINCT n1+n2 FROM t1;
id select_type table type possible_keys key key_len ref rows Extra
# # # # # n1_n2 # # # #
SELECT DISTINCT n1+n2 FROM t1;
n1+n2
0.0000
100023.0000
123469.0000
123470.0000
123470.3456
25.0000
3.0000
DROP TABLE t1;
CREATE TABLE t1 (d1 DECIMAL(10,2) <CUSTOM_COL_OPTIONS>,
d2 DECIMAL(60,10) <CUSTOM_COL_OPTIONS>,
n1 NUMERIC <CUSTOM_COL_OPTIONS>,
n2 NUMERIC(65,4) <CUSTOM_COL_OPTIONS>,
INDEX (d2)
) ENGINE=<STORAGE_ENGINE> <CUSTOM_TABLE_OPTIONS>;
SHOW INDEX IN t1;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment
t1 1 d2 1 d2 # # NULL NULL # #
INSERT INTO t1 (d1,d2,n1,n2) VALUES
(10.22,60.12345,123456,14.3456),
(10.0,60.12345,123456,14),
(11.14,15,123456,13),
(100,100,1,2),
(0,0,0,0),
(4540424564.23,3343303441.0,12,13),
(15,17,23,100000);
Warnings:
Warning 1264 Out of range value for column 'd1' at row 6
EXPLAIN SELECT d2, COUNT(*) FROM t1 GROUP BY d2;
id select_type table type possible_keys key key_len ref rows Extra
# # # # # d2 # # # #
SELECT d2, COUNT(*) FROM t1 GROUP BY d2;
d2 COUNT(*)
0.0000000000 1
100.0000000000 1
15.0000000000 1
17.0000000000 1
3343303441.0000000000 1
60.1234500000 2
EXPLAIN SELECT d2, COUNT(*) FROM t1 IGNORE INDEX FOR GROUP BY (d2) GROUP BY d2;
id select_type table type possible_keys key key_len ref rows Extra
# # # # # d2 # # # #
SELECT d2, COUNT(*) FROM t1 IGNORE INDEX FOR GROUP BY (d2) GROUP BY d2;
d2 COUNT(*)
0.0000000000 1
100.0000000000 1
15.0000000000 1
17.0000000000 1
3343303441.0000000000 1
60.1234500000 2
DROP TABLE t1;
|
