多项选择题
A. cannot be nested
B. manipulate data items
C. act on each row returned
D. return one result per row
E. accept only one argument and return only one value
F. accept arguments which can be a column or an expression
单项选择题 Which describes the default behavior when you create a table? （）
单项选择题 The STUDENT_GRADES table has these columns: STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) The registrar requested a report listing the students grade point averages (GPA) sorted from highest grade point average to lowest. Which statement produces a report that displays the student ID and GPA in the sorted order requested by the registrar? （）
单项选择题 You need to modify the STUDENTS table to add a primary key on the STUDENT_ID column. The table is currently empty. Which statement accomplishes this task?（）