MySQL 8.0 参考手册  / 第 28 章 MySQL 系统模式  / 28.4 sys 模式对象参考  / 28.4.5 sys 模式存储函数  / 
28.4.5.12 ps_is_instrument_default_timed() 函数	
            
          返回YES或NO指示给定的 Performance Schema 工具是否默认计时。
mysql> SELECT sys.ps_is_instrument_default_timed('memory/innodb/row_log_buf');
+-----------------------------------------------------------------+
| sys.ps_is_instrument_default_timed('memory/innodb/row_log_buf') |
+-----------------------------------------------------------------+
| NO                                                              |
+-----------------------------------------------------------------+
mysql> SELECT sys.ps_is_instrument_default_timed('statement/sql/alter_user');
+----------------------------------------------------------------+
| sys.ps_is_instrument_default_timed('statement/sql/alter_user') |
+----------------------------------------------------------------+
| YES                                                            |
+----------------------------------------------------------------+