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
149
150
151
152
153
154
155
|
SELECT logged INTO @startup
FROM performance_schema.error_log
WHERE error_code="MY-010116" ORDER BY logged DESC LIMIT 1;
====================================================================
Testing index for columns LOGGED
====================================================================
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE LOGGED = @startup;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL const PRIMARY PRIMARY 7 const # 100.00 NULL
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE LOGGED > @startup;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE LOGGED < @startup;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL PRIMARY NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE LOGGED != @startup;
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL PRIMARY NULL NULL NULL # 90.00 Using where
############# Explain End #########################################
====================================================================
Testing index for columns THREAD_ID
====================================================================
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE THREAD_ID = "0";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ref THREAD_ID THREAD_ID 9 const # 100.00 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE THREAD_ID > "0";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL THREAD_ID NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE THREAD_ID < "0";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL # NULL Impossible WHERE
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE THREAD_ID != "0";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL THREAD_ID NULL NULL NULL # 90.00 Using where
############# Explain End #########################################
====================================================================
Testing index for columns PRIO
====================================================================
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE PRIO = "System";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ref PRIO PRIO 1 const # 100.00 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE PRIO > "System";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL PRIO NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE PRIO < "System";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL PRIO NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE PRIO != "System";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL PRIO NULL NULL NULL # 75.00 Using where
############# Explain End #########################################
====================================================================
Testing index for columns ERROR_CODE
====================================================================
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE ERROR_CODE = "MY-010116";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ref ERROR_CODE ERROR_CODE 43 const # 100.00 NULL
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE ERROR_CODE > "MY-010116";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL ERROR_CODE NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE ERROR_CODE < "MY-010116";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL ERROR_CODE NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE ERROR_CODE != "MY-010116";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL ERROR_CODE NULL NULL NULL # 90.00 Using where
############# Explain End #########################################
====================================================================
Testing index for columns SUBSYSTEM
====================================================================
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE SUBSYSTEM = "Server";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ref SUBSYSTEM SUBSYSTEM 31 const # 100.00 NULL
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE SUBSYSTEM > "Server";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL SUBSYSTEM NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE SUBSYSTEM < "Server";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL SUBSYSTEM NULL NULL NULL # 33.33 Using where
############ Explain for Query ####################################
EXPLAIN SELECT ERROR_CODE
FROM performance_schema.error_log
WHERE SUBSYSTEM != "Server";
id select_type table partitions type possible_keys key key_len ref rows filtered Extra
1 SIMPLE error_log NULL ALL SUBSYSTEM NULL NULL NULL # 90.00 Using where
############# Explain End #########################################
#
# read key
#
FLUSH STATUS;
SELECT COUNT(ERROR_CODE) FROM performance_schema.error_log WHERE LOGGED = @startup;
OK: handler_read_key incremented
|
