|
1
by brian
clean slate |
1 |
flush status; |
2 |
show status like 'Table_lock%'; |
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3 |
Variable_name Value |
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4 |
Table_locks_immediate 1 |
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5 |
Table_locks_waited 0 |
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6 |
select * from information_schema.session_status where variable_name like 'Table_lock%'; |
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7 |
VARIABLE_NAME VARIABLE_VALUE |
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8 |
TABLE_LOCKS_IMMEDIATE 2 |
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9 |
TABLE_LOCKS_WAITED 0 |
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10 |
SET SQL_LOG_BIN=0; |
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11 |
set @old_general_log = @@global.general_log; |
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12 |
set global general_log = 'OFF'; |
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13 |
drop table if exists t1; |
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14 |
create table t1(n int) engine=myisam; |
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15 |
insert into t1 values(1); |
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16 |
lock tables t1 read; |
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17 |
unlock tables; |
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18 |
lock tables t1 read; |
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19 |
update t1 set n = 3; |
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20 |
unlock tables; |
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21 |
show status like 'Table_locks_waited'; |
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22 |
Variable_name Value |
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23 |
Table_locks_waited 1 |
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24 |
drop table t1; |
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25 |
set global general_log = @old_general_log; |
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26 |
select 1; |
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27 |
1
|
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28 |
1
|
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29 |
show status like 'last_query_cost'; |
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30 |
Variable_name Value |
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31 |
Last_query_cost 0.000000 |
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32 |
create table t1 (a int); |
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33 |
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10); |
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34 |
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10); |
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35 |
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10); |
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36 |
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10); |
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37 |
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10); |
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38 |
select * from t1 where a=6; |
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39 |
a
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40 |
6
|
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41 |
6
|
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42 |
6
|
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43 |
6
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44 |
6
|
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45 |
show status like 'last_query_cost'; |
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46 |
Variable_name Value |
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47 |
Last_query_cost 12.084449 |
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48 |
show status like 'last_query_cost'; |
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49 |
Variable_name Value |
|
50 |
Last_query_cost 12.084449 |
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51 |
select 1; |
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52 |
1
|
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53 |
1
|
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54 |
show status like 'last_query_cost'; |
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55 |
Variable_name Value |
|
56 |
Last_query_cost 0.000000 |
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57 |
drop table t1; |
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58 |
FLUSH STATUS; |
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59 |
SHOW STATUS LIKE 'max_used_connections'; |
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60 |
Variable_name Value |
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61 |
Max_used_connections 1 |
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62 |
SELECT * FROM INFORMATION_SCHEMA.SESSION_STATUS WHERE VARIABLE_NAME LIKE 'max_used_connections'; |
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63 |
VARIABLE_NAME VARIABLE_VALUE |
|
64 |
MAX_USED_CONNECTIONS 1 |
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65 |
SET @save_thread_cache_size=@@thread_cache_size; |
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66 |
SET GLOBAL thread_cache_size=3; |
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67 |
SHOW STATUS LIKE 'max_used_connections'; |
|
68 |
Variable_name Value |
|
69 |
Max_used_connections 3 |
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70 |
SELECT * FROM INFORMATION_SCHEMA.SESSION_STATUS WHERE VARIABLE_NAME LIKE 'max_used_connections'; |
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71 |
VARIABLE_NAME VARIABLE_VALUE |
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72 |
MAX_USED_CONNECTIONS 3 |
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73 |
FLUSH STATUS; |
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74 |
SHOW STATUS LIKE 'max_used_connections'; |
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75 |
Variable_name Value |
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76 |
Max_used_connections 2 |
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77 |
SELECT * FROM INFORMATION_SCHEMA.SESSION_STATUS WHERE VARIABLE_NAME LIKE 'max_used_connections'; |
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78 |
VARIABLE_NAME VARIABLE_VALUE |
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79 |
MAX_USED_CONNECTIONS 2 |
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80 |
SHOW STATUS LIKE 'max_used_connections'; |
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81 |
Variable_name Value |
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82 |
Max_used_connections 3 |
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83 |
SELECT * FROM INFORMATION_SCHEMA.SESSION_STATUS WHERE VARIABLE_NAME LIKE 'max_used_connections'; |
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84 |
VARIABLE_NAME VARIABLE_VALUE |
|
85 |
MAX_USED_CONNECTIONS 3 |
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86 |
SHOW STATUS LIKE 'max_used_connections'; |
|
87 |
Variable_name Value |
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88 |
Max_used_connections 4 |
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89 |
SELECT * FROM INFORMATION_SCHEMA.SESSION_STATUS WHERE VARIABLE_NAME LIKE 'max_used_connections'; |
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90 |
VARIABLE_NAME VARIABLE_VALUE |
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91 |
MAX_USED_CONNECTIONS 4 |
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92 |
SET GLOBAL thread_cache_size=@save_thread_cache_size; |
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93 |
CREATE TABLE t1 ( a INT ); |
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94 |
INSERT INTO t1 VALUES (1), (2); |
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95 |
SELECT a FROM t1 LIMIT 1; |
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96 |
a
|
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97 |
1
|
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98 |
SHOW SESSION STATUS LIKE 'Last_query_cost'; |
|
99 |
Variable_name Value |
|
100 |
Last_query_cost 2.402418 |
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101 |
EXPLAIN SELECT a FROM t1; |
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102 |
id select_type table type possible_keys key key_len ref rows Extra |
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103 |
1 SIMPLE t1 ALL NULL NULL NULL NULL 2 |
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104 |
SHOW SESSION STATUS LIKE 'Last_query_cost'; |
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105 |
Variable_name Value |
|
106 |
Last_query_cost 2.402418 |
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107 |
SELECT a FROM t1 UNION SELECT a FROM t1 ORDER BY a; |
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108 |
a
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109 |
1
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110 |
2
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111 |
SHOW SESSION STATUS LIKE 'Last_query_cost'; |
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112 |
Variable_name Value |
|
113 |
Last_query_cost 0.000000 |
|
114 |
EXPLAIN SELECT a FROM t1 UNION SELECT a FROM t1 ORDER BY a; |
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115 |
id select_type table type possible_keys key key_len ref rows Extra |
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116 |
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 |
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117 |
2 UNION t1 ALL NULL NULL NULL NULL 2 |
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118 |
NULL UNION RESULT <union1,2> ALL NULL NULL NULL NULL NULL Using filesort |
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119 |
SHOW SESSION STATUS LIKE 'Last_query_cost'; |
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120 |
Variable_name Value |
|
121 |
Last_query_cost 0.000000 |
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122 |
SELECT a IN (SELECT a FROM t1) FROM t1 LIMIT 1; |
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123 |
a IN (SELECT a FROM t1) |
|
124 |
1
|
|
125 |
SHOW SESSION STATUS LIKE 'Last_query_cost'; |
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126 |
Variable_name Value |
|
127 |
Last_query_cost 0.000000 |
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128 |
SELECT (SELECT a FROM t1 LIMIT 1) x FROM t1 LIMIT 1; |
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129 |
x
|
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130 |
1
|
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131 |
SHOW SESSION STATUS LIKE 'Last_query_cost'; |
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132 |
Variable_name Value |
|
133 |
Last_query_cost 0.000000 |
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134 |
SELECT * FROM t1 a, t1 b LIMIT 1; |
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135 |
a a |
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136 |
1 1 |
|
137 |
SHOW SESSION STATUS LIKE 'Last_query_cost'; |
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138 |
Variable_name Value |
|
139 |
Last_query_cost 4.805836 |
|
140 |
DROP TABLE t1; |
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141 |
show status like 'com_show_status'; |
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142 |
Variable_name Value |
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143 |
Com_show_status 3 |
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144 |
show status like 'hand%write%'; |
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145 |
Variable_name Value |
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146 |
Handler_write 5 |
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147 |
show status like '%tmp%'; |
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148 |
Variable_name Value |
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149 |
Created_tmp_disk_tables 0 |
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150 |
Created_tmp_files 0 |
|
151 |
Created_tmp_tables 0 |
|
152 |
show status like 'hand%write%'; |
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153 |
Variable_name Value |
|
154 |
Handler_write 7 |
|
155 |
show status like '%tmp%'; |
|
156 |
Variable_name Value |
|
157 |
Created_tmp_disk_tables 0 |
|
158 |
Created_tmp_files 0 |
|
159 |
Created_tmp_tables 0 |
|
160 |
show status like 'com_show_status'; |
|
161 |
Variable_name Value |
|
162 |
Com_show_status 8 |
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163 |
rnd_diff tmp_table_diff |
|
164 |
20 8 |
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165 |
show global status like 'Com%function%'; |
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166 |
Variable_name Value |
|
167 |
Com_alter_function 0 |
|
168 |
Com_create_function 0 |
|
169 |
Com_drop_function 0 |
|
170 |
Com_show_function_code 0 |
|
171 |
Com_show_function_status 0 |
|
172 |
create function f1 (x INTEGER) returns integer |
|
173 |
begin
|
|
174 |
declare ret integer; |
|
175 |
set ret = x * 10; |
|
176 |
return ret; |
|
177 |
end // |
|
178 |
drop function f1; |
|
179 |
show global status like 'Com%function%'; |
|
180 |
Variable_name Value |
|
181 |
Com_alter_function 0 |
|
182 |
Com_create_function 1 |
|
183 |
Com_drop_function 1 |
|
184 |
Com_show_function_code 0 |
|
185 |
Com_show_function_status 0 |
|
186 |
SELECT VARIABLE_VALUE INTO @tc FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'Threads_connected'; |
|
187 |
SELECT VARIABLE_NAME FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'Threads_created' AND VARIABLE_VALUE < @tc; |
|
188 |
VARIABLE_NAME
|
|
189 |
SELECT VARIABLE_VALUE INTO @tr FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'Threads_running'; |
|
190 |
FLUSH STATUS; |
|
191 |
SELECT * FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'Threads_connected' AND VARIABLE_VALUE < @tc; |
|
192 |
VARIABLE_NAME VARIABLE_VALUE |
|
193 |
SELECT * FROM INFORMATION_SCHEMA.GLOBAL_STATUS WHERE VARIABLE_NAME = 'Threads_running' AND VARIABLE_VALUE < @tr; |
|
194 |
VARIABLE_NAME VARIABLE_VALUE |