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在关系SC(student_id,student_name,course_id,grade)中,有 student_id,course_id→grade student_id→student_name 关系SC最高达到______范式。

A.不满足

B.1NF

C.2NF

D.3NF


参考答案

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考题 单选题The STUDENT_GRADES table has these columns: STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) The register has requested a report listing the students' grade point averages (GPA), sorted from highest grade point average to lowest within each semester, starting from the earliest date. Which statement accomplishes this?()A SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester_end DESC, gpa DESC;B SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester _end, ASC,gpa ASC;C SELECT student_id, semester_end, gpa FROM student_grades ORDER BY semester _end, gpa DESC;D SELECT student_id, semester_end, gpa FROM student_grades ORDER BY gpa DESC,semester_end DESC;E SELECT student_id, semester_end, gpa FROM student_grades

考题 单选题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?()A SELECT student_id, gpa FROM student_grades ORDER BY gpa ASC;B SELECT student_id, gpa FROM student_grades SORT ORDER BY gpa ASC;C SELECT student_id, gpa FROM student_grades SORT ORDER BY gpa;D SELECT student_id, gpa FROM student_grades ORDER BY gpa;E SELECT student_id, gpa FROM student_grades SORT ORDER BY gpa DESC;F SELECT student_id, gpa FROM student_grades ORDER BY gpa DESC;

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