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|
# ulong session
SET @start_global_value = @@global.join_cache_level;
#
# exists as global only
#
select @@global.join_cache_level;
select @@session.join_cache_level;
show global variables like 'join_cache_level';
show session variables like 'join_cache_level';
select * from information_schema.global_variables where variable_name='join_cache_level';
select * from information_schema.session_variables where variable_name='join_cache_level';
#
# show that it's writable
#
set global join_cache_level=4;
select @@global.join_cache_level;
set session join_cache_level=4;
select @@session.join_cache_level;
#
# incorrect types
#
--error ER_WRONG_TYPE_FOR_VAR
set global join_cache_level=1.1;
--error ER_WRONG_TYPE_FOR_VAR
set session join_cache_level=1e1;
--error ER_WRONG_TYPE_FOR_VAR
set global join_cache_level="foo";
#
# min/max values, block size
#
set global join_cache_level=0;
select @@global.join_cache_level;
set session join_cache_level=cast(-1 as unsigned int);
select @@session.join_cache_level;
SET @@global.join_cache_level = @start_global_value;
|
