select @@global.named_pipe;
@@global.named_pipe
0
select @@session.named_pipe;
ERROR HY000: Variable 'named_pipe' is a GLOBAL variable
show global variables like 'named_pipe';
Variable_name	Value
named_pipe	OFF
show session variables like 'named_pipe';
Variable_name	Value
named_pipe	OFF
select * from information_schema.global_variables where variable_name='named_pipe';
VARIABLE_NAME	VARIABLE_VALUE
NAMED_PIPE	OFF
select * from information_schema.session_variables where variable_name='named_pipe';
VARIABLE_NAME	VARIABLE_VALUE
NAMED_PIPE	OFF
set global named_pipe=1;
ERROR HY000: Variable 'named_pipe' is a read only variable
set session named_pipe=1;
ERROR HY000: Variable 'named_pipe' is a read only variable