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--source include/default_optimizer_switch.inc
#
# 2010-01-20 OBN Added check for I_S values after variable value changed
#
set @@global.optimizer_switch=@@optimizer_switch;
#
# exists as global and session
#
select @@global.optimizer_switch;
select @@session.optimizer_switch;
show global variables like 'optimizer_switch';
show session variables like 'optimizer_switch';
select * from information_schema.global_variables where variable_name='optimizer_switch';
select * from information_schema.session_variables where variable_name='optimizer_switch';
#
# show that it's writable
#
set global optimizer_switch=4101;
set session optimizer_switch=2058;
select @@global.optimizer_switch;
select @@session.optimizer_switch;
set global optimizer_switch="index_merge_sort_union=on";
set session optimizer_switch="index_merge=off";
select @@global.optimizer_switch;
select @@session.optimizer_switch;
show global variables like 'optimizer_switch';
show session variables like 'optimizer_switch';
select * from information_schema.global_variables where variable_name='optimizer_switch';
select * from information_schema.session_variables where variable_name='optimizer_switch';
set session optimizer_switch="default";
select @@session.optimizer_switch;
set optimizer_switch = replace(@@optimizer_switch, '=off', '=on');
select @@optimizer_switch;
#
# incorrect assignments
#
--error ER_WRONG_TYPE_FOR_VAR
set global optimizer_switch=1.1;
--error ER_WRONG_TYPE_FOR_VAR
set global optimizer_switch=1e1;
--error ER_WRONG_VALUE_FOR_VAR
set session optimizer_switch="index_merge";
--error ER_WRONG_VALUE_FOR_VAR
set session optimizer_switch="foobar";
SET @@global.optimizer_switch = @save_optimizer_switch;
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