select @@global.lower_case_table_names=20; @@global.lower_case_table_names=20 0 select @@session.lower_case_table_names; ERROR HY000: Variable 'lower_case_table_names' is a GLOBAL variable SELECT @@global.lower_case_table_names in (0,1,2); @@global.lower_case_table_names in (0,1,2) 1 SELECT @@global.lower_case_table_names = VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES WHERE VARIABLE_NAME='lower_case_table_names'; @@global.lower_case_table_names = VARIABLE_VALUE 1 SELECT @@global.lower_case_table_names = VARIABLE_VALUE FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES WHERE VARIABLE_NAME='lower_case_table_names'; @@global.lower_case_table_names = VARIABLE_VALUE 1 set global lower_case_table_names=1; ERROR HY000: Variable 'lower_case_table_names' is a read only variable set session lower_case_table_names=1; ERROR HY000: Variable 'lower_case_table_names' is a read only variable