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#
# 2010-01-20 - OBN - Added check for variable value sameas I_S table
# after variable value change
#
SET @start_global_value = @@global.max_join_size;
SELECT @start_global_value;
#
# exists as global and session
#
select @@global.max_join_size;
select @@session.max_join_size;
show global variables like 'max_join_size';
show session variables like 'max_join_size';
select * from information_schema.global_variables where variable_name='max_join_size';
select * from information_schema.session_variables where variable_name='max_join_size';
#
# show that it's writable
#
set global max_join_size=10;
set session max_join_size=20;
select @@global.max_join_size;
select @@session.max_join_size;
show global variables like 'max_join_size';
show session variables like 'max_join_size';
select * from information_schema.global_variables where variable_name='max_join_size';
select * from information_schema.session_variables where variable_name='max_join_size';
#
# incorrect types
#
--error ER_WRONG_TYPE_FOR_VAR
set global max_join_size=1.1;
--error ER_WRONG_TYPE_FOR_VAR
set global max_join_size=1e1;
--error ER_WRONG_TYPE_FOR_VAR
set global max_join_size="foo";
#
# affects OPTION_BIG_SELECTS
#
select @@sql_big_selects;
set max_join_size=cast(-1 as unsigned int);
select @@sql_big_selects;
set max_join_size=100;
select @@sql_big_selects;
SET @@global.max_join_size = @start_global_value;
SELECT @@global.max_join_size;
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