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|
'#---------------------WL6372_VAR_8_01----------------------#'
SELECT COUNT(@@GLOBAL.sort_buffer_size);
COUNT(@@GLOBAL.sort_buffer_size)
1
SELECT COUNT(@@SESSION.sort_buffer_size);
COUNT(@@SESSION.sort_buffer_size)
1
SELECT @@GLOBAL.sort_buffer_size;
@@GLOBAL.sort_buffer_size
262144
SELECT @@SESSION.sort_buffer_size;
@@SESSION.sort_buffer_size
262144
'#---------------------WL6372_VAR_8_02----------------------#'
# Restart server with sort_buffer_size 9999999;
# restart:--sort_buffer_size=9999999
SELECT @@GLOBAL.sort_buffer_size;
@@GLOBAL.sort_buffer_size
9999999
SET @@GLOBAL.sort_buffer_size=DEFAULT;
SELECT @@GLOBAL.sort_buffer_size;
@@GLOBAL.sort_buffer_size
262144
'#---------------------WL6372_VAR_8_03----------------------#'
SET @@local.sort_buffer_size=9999999;
SET @@session.sort_buffer_size=9999999;
SET @@GLOBAL.sort_buffer_size=9999999;
SET @@local.sort_buffer_size=DEFAULT;
SET @@session.sort_buffer_size=DEFAULT;
SET @@GLOBAL.sort_buffer_size=DEFAULT;
SELECT @@GLOBAL.sort_buffer_size;
@@GLOBAL.sort_buffer_size
262144
'#---------------------WL6372_VAR_8_04----------------------#'
SELECT @@GLOBAL.sort_buffer_size = VARIABLE_VALUE
FROM performance_schema.global_variables
WHERE VARIABLE_NAME='sort_buffer_size';
@@GLOBAL.sort_buffer_size = VARIABLE_VALUE
1
SELECT @@session.sort_buffer_size = VARIABLE_VALUE
FROM performance_schema.session_variables
WHERE VARIABLE_NAME='sort_buffer_size';
@@session.sort_buffer_size = VARIABLE_VALUE
1
SELECT COUNT(@@GLOBAL.sort_buffer_size);
COUNT(@@GLOBAL.sort_buffer_size)
1
SELECT COUNT(VARIABLE_VALUE)
FROM performance_schema.global_variables
WHERE VARIABLE_NAME='sort_buffer_size';
COUNT(VARIABLE_VALUE)
1
'#---------------------WL6372_VAR_8_05----------------------#'
SELECT @@sort_buffer_size = @@GLOBAL.sort_buffer_size;
@@sort_buffer_size = @@GLOBAL.sort_buffer_size
0
SELECT COUNT(@@sort_buffer_size);
COUNT(@@sort_buffer_size)
1
SELECT COUNT(@@local.sort_buffer_size);
COUNT(@@local.sort_buffer_size)
1
SELECT COUNT(@@SESSION.sort_buffer_size);
COUNT(@@SESSION.sort_buffer_size)
1
SELECT COUNT(@@GLOBAL.sort_buffer_size);
COUNT(@@GLOBAL.sort_buffer_size)
1
SELECT sort_buffer_size = @@SESSION.sort_buffer_size;
ERROR 42S22: Unknown column 'sort_buffer_size' in 'field list'
'#---------------------WL6372_VAR_8_06----------------------#'
SET @@GLOBAL.sort_buffer_size=32767;
SET @@session.sort_buffer_size=32767;
SELECT @@GLOBAL.sort_buffer_size;
@@GLOBAL.sort_buffer_size
32768
select @@session.sort_buffer_size;
@@session.sort_buffer_size
32768
SET @@global.sort_buffer_size=-1;
SET @@session.sort_buffer_size=-1;
select @@session.sort_buffer_size;
@@session.sort_buffer_size
32768
SELECT @@GLOBAL.sort_buffer_size;
@@GLOBAL.sort_buffer_size
32768
'#---------------------WL6372_VAR_8_07----------------------#'
Check the size of the vardir
The output size is in unit blocks
TRUE
'#---------------------WL6372_VAR_8_08----------------------#'
# create a table
===============
create table & Index
===============
CREATE TABLE tab1 (col_1 text(10))
ENGINE=INNODB ;
#insert some 10 records
===============
Load the data
===============
SET @col_1 = repeat('a', 10);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
INSERT INTO tab1
VALUES (@col_1);
commit;
flush status;
flush table;
SET @@GLOBAL.sort_buffer_size=32768;
SET @@SESSION.sort_buffer_size=32768;
select variable_value from performance_schema.session_status where variable_name ='Sort_merge_passes';
variable_value
0
select variable_value from performance_schema.session_status where variable_name ='Sort_rows';
variable_value
0
select variable_value from performance_schema.session_status where variable_name ='Sort_scan';
variable_value
0
set @Sort_merge_passes = (select variable_value from performance_schema.session_status where variable_name ='Sort_merge_passes');
set @Sort_rows = (select variable_value from performance_schema.session_status where variable_name ='Sort_rows');
set @Sort_scan = (select variable_value from performance_schema.session_status where variable_name ='Sort_scan');
set @optimizer_switch_saved=@@optimizer_switch;
set optimizer_switch='derived_merge=off';
select count(1) from (select b.* from tab1 b inner join tab1 c inner join tab1 d inner join tab1 e inner join tab1 f order by 1) a;
count(1)
100000
select ( select variable_value from performance_schema.global_status where variable_name ='Sort_merge_passes') - @Sort_merge_passes;
( select variable_value from performance_schema.global_status where variable_name ='Sort_merge_passes') - @Sort_merge_passes
24
select (select variable_value from performance_schema.global_status where variable_name ='Sort_rows') - @Sort_rows;
(select variable_value from performance_schema.global_status where variable_name ='Sort_rows') - @Sort_rows
100000
select (select variable_value from performance_schema.global_status where variable_name ='Sort_scan') - @Sort_scan;
(select variable_value from performance_schema.global_status where variable_name ='Sort_scan') - @Sort_scan
1
select count(1) from (select b.* from tab1 b inner join tab1 c inner join tab1 d inner join tab1 e inner join tab1 f order by 1) a;
count(1)
100000
select ( select variable_value from performance_schema.global_status where variable_name ='Sort_merge_passes') - @Sort_merge_passes;
( select variable_value from performance_schema.global_status where variable_name ='Sort_merge_passes') - @Sort_merge_passes
48
select (select variable_value from performance_schema.global_status where variable_name ='Sort_rows') - @Sort_rows;
(select variable_value from performance_schema.global_status where variable_name ='Sort_rows') - @Sort_rows
200000
select (select variable_value from performance_schema.global_status where variable_name ='Sort_scan') - @Sort_scan;
(select variable_value from performance_schema.global_status where variable_name ='Sort_scan') - @Sort_scan
2
set @@optimizer_switch=@optimizer_switch_saved;
#cleanup
DROP TABLE IF EXISTS tab1;
SET @@session.sort_buffer_size=DEFAULT;
SET @@GLOBAL.sort_buffer_size=DEFAULT;
|
