1select @@global.have_profiling="1"; 2@@global.have_profiling="1" 30 4Warnings: 5Warning 1287 '@@have_profiling' is deprecated and will be removed in a future release. 6select @@session.have_profiling; 7ERROR HY000: Variable 'have_profiling' is a GLOBAL variable 8show global variables like 'have_profiling'; 9Variable_name Value 10have_profiling # 11show session variables like 'have_profiling'; 12Variable_name Value 13have_profiling # 14select * from information_schema.global_variables where variable_name='have_profiling'; 15VARIABLE_NAME VARIABLE_VALUE 16HAVE_PROFILING # 17select * from information_schema.session_variables where variable_name='have_profiling'; 18VARIABLE_NAME VARIABLE_VALUE 19HAVE_PROFILING # 20set global have_profiling=1; 21ERROR HY000: Variable 'have_profiling' is a read only variable 22set session have_profiling=1; 23ERROR HY000: Variable 'have_profiling' is a read only variable 24