1# Displaying default value 2SELECT COUNT(@@GLOBAL.have_statement_timeout); 3COUNT(@@GLOBAL.have_statement_timeout) 41 51 Expected 6# Check if Value can set 7SET @@GLOBAL.have_statement_timeout=1; 8ERROR HY000: Variable 'have_statement_timeout' is a read only variable 9Expected error 'Read only variable' 10SELECT COUNT(@@GLOBAL.have_statement_timeout); 11COUNT(@@GLOBAL.have_statement_timeout) 121 131 Expected 14# Check if the value in GLOBAL Table matches value in variable 15SELECT @@GLOBAL.have_statement_timeout = VARIABLE_VALUE 16FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES 17WHERE VARIABLE_NAME='have_statement_timeout'; 18@@GLOBAL.have_statement_timeout = VARIABLE_VALUE 191 201 Expected 21SELECT COUNT(@@GLOBAL.have_statement_timeout); 22COUNT(@@GLOBAL.have_statement_timeout) 231 241 Expected 25SELECT COUNT(VARIABLE_VALUE) 26FROM INFORMATION_SCHEMA.GLOBAL_VARIABLES 27WHERE VARIABLE_NAME='have_statement_timeout'; 28COUNT(VARIABLE_VALUE) 291 301 Expected 31# Check if accessing variable with and without GLOBAL point to same variable 32SELECT @@have_statement_timeout = @@GLOBAL.have_statement_timeout; 33@@have_statement_timeout = @@GLOBAL.have_statement_timeout 341 351 Expected 36# Check if have_statement_timeout can be accessed with and without @@ sign 37SELECT COUNT(@@have_statement_timeout); 38COUNT(@@have_statement_timeout) 391 401 Expected 41SELECT COUNT(@@local.have_statement_timeout); 42ERROR HY000: Variable 'have_statement_timeout' is a GLOBAL variable 43Expected error 'Variable is a GLOBAL variable' 44SELECT COUNT(@@SESSION.have_statement_timeout); 45ERROR HY000: Variable 'have_statement_timeout' is a GLOBAL variable 46Expected error 'Variable is a GLOBAL variable' 47SELECT COUNT(@@GLOBAL.have_statement_timeout); 48COUNT(@@GLOBAL.have_statement_timeout) 491 501 Expected 51SELECT have_statement_timeout = @@SESSION.have_statement_timeout; 52ERROR 42S22: Unknown column 'have_statement_timeout' in 'field list' 53Expected error 'Readonly variable' 54