====== 5.5 Oracles ======
[[dido:public:s_cli:05_contents:01_prt:04_dll:start| Return to DidoDLL]]

<code SQL>
 CREATE oracle OurDido.StudentStatement 
      FROM OurDido.StudentAccount
        TO MyDido.Student
       ( StudentStatementId : Hash,
         StudentId : SELECT genesis  
                       FROM MyDido.Student    STUDENT 
                      WHERE STUDENT.StudentId = $1.,
         AccountId : SELECT genesis  
                       FROM MyDido.StudentAccount ACCOUNT 
                      WHERE ACCOUNT.AccountId = $2.
       )
       AS UNION OF
       ( SELECT current  
           FROM MyDido.Student         
          WHERE MyDido.Student         = STUDENT.StudentId,
         SELECT current  
           FROM OurDido.StudentAccount 
          WHERE OurDido.StudentAccount = ACCOUNT.AccountId
       );

</code>