报错一

解决方法：listener.ora中增加如下代码段

SID_LIST_LISTENER =
   (SID_LIST =
     (SID_DESC =
       (GLOBAL_DBNAME = racdb)
       (ORACLE_HOME = /u01/app/oracle/product/19.3.0/dbhome_1)
       (SID_NAME = racdb)
     )

   )

报错二

解决方法：alter system register;