| Server IP : 185.86.78.101 / Your IP : 216.73.216.213 Web Server : Apache System : Linux 675867-vds-valikoshka1996.gmhost.pp.ua 5.4.0-150-generic #167-Ubuntu SMP Mon May 15 17:35:05 UTC 2023 x86_64 User : www ( 1000) PHP Version : 7.4.33 Disable Function : passthru,exec,system,putenv,chroot,chgrp,chown,shell_exec,popen,proc_open,pcntl_exec,ini_alter,ini_restore,dl,openlog,syslog,readlink,symlink,popepassthru,pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wifcontinued,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,imap_open,apache_setenv MySQL : OFF | cURL : ON | WGET : ON | Perl : ON | Python : OFF | Sudo : ON | Pkexec : OFF Directory : /www/server/mysql/mysql-test/r/ |
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drop table if exists t1, t2;
create table t1 (
a int not null auto_increment,
b char(16) not null,
primary key (a),
key (b)
);
create table t2(
a int not null auto_increment,
b char(16) not null,
primary key (a),
key (b)
);
insert into t1(b) values
('test0'),
('test1'),
('test2'),
('test3'),
('test4'),
('test5'),
('test6'),
('test7');
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
insert into t2(b) select b from t1;
insert into t1(b) select b from t2;
select count(*) from t1;
count(*)
33448
select count(*) from t2;
count(*)
20672
flush tables;
flush status;
show status like "key_read%";
Variable_name Value
Key_read_requests 0
Key_reads 0
select count(*) from t1 where b = 'test1';
count(*)
4181
show status like "key_read%";
Variable_name Value
Key_read_requests 294
Key_reads 60
select count(*) from t1 where b = 'test1';
count(*)
4181
show status like "key_read%";
Variable_name Value
Key_read_requests 588
Key_reads 60
flush tables;
flush status;
select @@preload_buffer_size;
@@preload_buffer_size
32768
load index into cache t1;
Table Op Msg_type Msg_text
test.t1 preload_keys status OK
show status like "key_read%";
Variable_name Value
Key_read_requests 774
Key_reads 774
select count(*) from t1 where b = 'test1';
count(*)
4181
show status like "key_read%";
Variable_name Value
Key_read_requests 1068
Key_reads 774
flush tables;
flush status;
show status like "key_read%";
Variable_name Value
Key_read_requests 0
Key_reads 0
set session preload_buffer_size=256*1024;
select @@preload_buffer_size;
@@preload_buffer_size
262144
load index into cache t1 ignore leaves;
Table Op Msg_type Msg_text
test.t1 preload_keys status OK
show status like "key_read%";
Variable_name Value
Key_read_requests 17
Key_reads 17
select count(*) from t1 where b = 'test1';
count(*)
4181
show status like "key_read%";
Variable_name Value
Key_read_requests 311
Key_reads 75
flush tables;
flush status;
show status like "key_read%";
Variable_name Value
Key_read_requests 0
Key_reads 0
set session preload_buffer_size=1*1024;
select @@preload_buffer_size;
@@preload_buffer_size
1024
load index into cache t1, t2 key (primary,b) ignore leaves;
Table Op Msg_type Msg_text
test.t1 preload_keys status OK
test.t2 preload_keys status OK
show status like "key_read%";
Variable_name Value
Key_read_requests 785
Key_reads 785
select count(*) from t1 where b = 'test1';
count(*)
4181
select count(*) from t2 where b = 'test1';
count(*)
2584
show status like "key_read%";
Variable_name Value
Key_read_requests 1266
Key_reads 821
flush tables;
flush status;
show status like "key_read%";
Variable_name Value
Key_read_requests 0
Key_reads 0
load index into cache t3, t2 key (primary,b) ;
Table Op Msg_type Msg_text
test.t3 preload_keys Error Table 'test.t3' doesn't exist
test.t3 preload_keys status Operation failed
test.t2 preload_keys status OK
show status like "key_read%";
Variable_name Value
Key_read_requests 478
Key_reads 478
flush tables;
flush status;
show status like "key_read%";
Variable_name Value
Key_read_requests 0
Key_reads 0
load index into cache t3 key (b), t2 key (c) ;
Table Op Msg_type Msg_text
test.t3 preload_keys Error Table 'test.t3' doesn't exist
test.t3 preload_keys status Operation failed
test.t2 preload_keys Error Key 'c' doesn't exist in table 't2'
test.t2 preload_keys status Operation failed
show status like "key_read%";
Variable_name Value
Key_read_requests 0
Key_reads 0
drop table t1, t2;