我在Oracle Database 19 c Enterprise Edition Release 19.0.0.0.0数据库中执行以下sql Alter USER test_user2 GRANT CONNECT THROUGH test_user1 ROLE myTestRole1;，并运行到以下错误：

Error starting at line : 1 in command -
Alter USER test_user2 GRANT CONNECT THROUGH test_user1 ROLE myTestRole1
Error report -
ORA-00933: SQL command not properly ended
00933. 00000 -  "SQL command not properly ended"
*Cause:    
*Action:

在ROLE字中得到syntax error partially recognized rules railroad diagrams提示符。
当我检查文档时，语法是正确的，我拥有所有的grant、alter user和GRANT CONNECT THROUGH权限，并且创建了用户test_user1和test_user2，还创建了角色myTestRole 1。
注意：-此sql Alter USER test_user2 GRANT CONNECT THROUGH test_user1运行成功。谁能帮我一下。谢谢！
已尝试执行此sql Alter USER test_user2 GRANT CONNECT THROUGH test_user1 ROLE myTestRole 1，但未收到SQL命令未正确结束错误。