oracle database - Why is this query showing error ORA-00923:

ora 923 Appear a error SQL Error [923] [42000]:. ORA-00923: FROM keyword not found where expected Below is the SQL : SELECT A.Agent_key, Sum(Total_Orders) FROM (SELECT A.Agent_key, Sum(Total_Orders)

orang mati 2d, このエラーはのようなにします SQL> select sysdate dual; select sysdate dual * 1でエラーがしました : ORA-00923: FROMキーワードがのに.