UPDATE .. FROM syntax difference in Sql Server and Oracle

There is syntactical difference in few operations in SQL in Oracel and Sql server

For example: UPDATE .. FROM

UPDATE students

     SET grade='A'

FROM students s 

INNER JOIN students_marks sm ON sm.student_id = s.student_id

WHERE sm.total_marks>80;

The above query syntax works in Sql Server but will fail in Oracle.

Below is the Oracle alternative.

UPDATE 

     (SELECT grade 

             FROM students s

             INNER JOIN students_marks sm ON sm.student_id = s.student_id

             WHERE sm.total_marks>80) t 

SET t.grade='A';

Below is the block diagram for the Oracle query