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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
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更多 “ 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.1NFC.2NFD.3NF ” 相关考题
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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?()A、ALTER TABLE students ADD PRIMARY KEY _ id;B、ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);C、ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;D、ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);E、ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
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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Examine the structure of the STUDENTS table: STUDENT_ID NUMBER NOT NULL, Primary Key STUDENT_NAME VARCHAR2(30) COURSE_ID VARCHAR2(10) NOT NULL MARKS NUMBER START_DATE DATE FINISH_DATE DATE You need to create a report of the 10 students who achieved the highest ranking in the course INT SQL and who completed the course in the year 1999. Which SQL statement accomplishes this task?()A
SELECT student_ id, marks, ROWNUM Rank FROM students WHERE ROWNUM = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC-99 AND course_id = 'INT_SQL' ORDER BY mark DESC;B
SELECT student_id, marks, ROWID Rank FROM students WHERE ROWID = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC-99' AND course_id = 'INT_SQL' ORDER BY mark;C
SELECT student_id, marks, ROWNUM Rank FROM (SELECT student_id, marks FROM students WHERE ROWNUM = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC- 99' AND course_id = 'INT_SQL' ORDER BY mark DESC;D
SELECT student_id, marks, ROWNUM Rank FROM (SELECT student_id, marks FROM students WHERE (finish_date BETWEEN '01-JAN-99 AND '31-DEC-99' AND course_id = 'INT_SQL' ORDER BY marks DESC) WHERE ROWNUM = 10;E
SELECT student id, marks, ROWNUM Rank FROM (SELECT student_id, marks FROM students ORDER BY marks) WHERE ROWNUM = 10 AND finish date BETWEEN '01-JAN-99' AND '31-DEC-99' AND course _ id 'INT_SQL';
考题
单选题Examine the structure of the STUDENTS table: STUDENT_ID NUMBER NOT NULL, Primary Key STUDENT_NAME VARCHAR2(30) COURSE_ID VARCHAR2(10) NOT NULL MARKS NUMBER START_DATE DATE FINISH_DATE DATE You need to create a report of the 10 students who achieved the highest ranking in the course INT SQL and who completed the course in the year 1999. Which SQL statement accomplishes this task? ()A
SELECT student_ id, marks, ROWNUM Rank FROM students WHERE ROWNUM = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC-99 AND course_id = 'INT_SQL' ORDER BY mark DESC;B
SELECT student_id, marks, ROWID Rank FROM students WHERE ROWID = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC-99' AND course_id = 'INT_SQL' ORDER BY mark;C
SELECT student_id, marks, ROWNUM Rank FROM (SELECT student_id, marks FROM students WHERE ROWNUM = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC- 99' AND course_id = 'INT_SQL' ORDER BY mark DESC;D
SELECT student_id, marks, ROWNUM Rank FROM (SELECT student_id, marks FROM students WHERE (finish_date BETWEEN '01-JAN-99 AND '31-DEC-99' AND course_id = 'INT_SQL' ORDER BY marks DESC) WHERE ROWNUM = 10;E
SELECT student id, marks, ROWNUM Rank FROM (SELECT student_id, marks FROM students ORDER BY marks) WHERE ROWNUM = 10 AND finish date BETWEEN '01-JAN-99' AND '31-DEC-99' AND course _ id 'INT_SQL';
考题
单选题Examine the structure of the STUDENTS table: STUDENT_ID NUMBER NOT NULL, Primary Key STUDENT_NAME VARCHAR2(30) COURSE_ID VARCHAR2(10) NOT NULL MARKS NUMBER START_DATE DATE FINISH_DATE DATE You need to create a report of the 10 students who achieved the highest ranking in the course INT SQL and who completed the course in the year 1999. Which SQL statement accomplishes this task?()A
SELECT student_ id, marks, ROWNUM Rank FROM students WHERE ROWNUM = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC-99' AND course_id = 'INT_SQL' ORDER BY marks DESC;B
SELECT student_id, marks, ROWID Rank FROM students WHERE ROWID = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC-99' AND course_id = 'INT_SQL' ORDER BY marks;C
SELECT student_id, marks, ROWNUM Rank FROM (SELECT student_id, marks FROM students WHERE ROWNUM = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC-99' AND course_id = 'INT_SQL' ORDER BY marks DESC);D
SELECT student_id, marks, ROWNUM Rank FROM (SELECT student_id, marks FROM students ORDER BY marks DESC) WHERE ROWNUM = 10 AND finish_date BETWEEN '01-JAN-99' AND '31-DEC-99' AND course _ id ='INT _ SQL';
考题
单选题Which statement explicitly names a constraint?()A
ALTER TABLE student_grades ADD FOREIGN KEY (student_id) REFERENCES students (student_id);B
ALTER TABLE student_grades ADD CONSTRAINT NAME = student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);C
ALTER TABLE student_grades ADD CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);D
ALTER TABLE student grades ADD NAMED CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);E
ALTER TABLE student grades ADD NAME student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id);
考题
单选题The STUDENT_GRADES table has these columns STUDENT_ID NUMBER(12) SEMESTER_END DATE GPA NUMBER(4,3) Which statement finds students who have a grade point average (GPA) greater than 3.0 for the calendar year 2001?()A
SELECT student_id, gpa FROM student_grades WHERE semester_end BETWEEN '01-JAN-2001' AND '31-DEC-2001' OR gpa 3.;B
SELECT student_id, gpa FROM student_grades WHERE semester_end BETWEEN '01-JAN-2001' AND '31-DEC-2001' AND gpa gt 3.0;C
SELECT student_id, gpa FROM student_grades WHERE semester_end BETWEEN '01-JAN-2001' AND '31-DEC-2001' AND gpa 3.0;D
SELECT student_id, gpa FROM student_grades WHERE semester_end '01-JAN-2001' OR semester_end '31-DEC-2001' AND gpa =s 3.0;
考题
单选题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?()A
ALTER TABLE students ADD PRIMARY KEY _ id;B
ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);C
ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;D
ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);E
ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
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;
考题
单选题You need to design a student registration database that contains several tables storing academic information. The STUDENTS table stores information about a student. The STUDENT_GRADES table stores information about the student's grades. Both of the tables have a column named STUDENT_ID. The STUDENT_ID column in the STUDENTS table is a primary key. You need to create a foreign key on the STUDENT_ID column of the STUDENT_GRADES table that points to the STUDENT_ID column of the STUDENTS table. Which statement creates the foreign key?()A
CREATE TABLE student_grades (student_id NUMBER(12),semester_end DATE, gpa NUMBER(4,3), CONSTRAINT student_id_fk REFERENCES (student_id) FOREIGN KEY student (student_id));B
CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa NUMBER(4,3), student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id));C
CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa NUMBER(4,3), CONSTRAINT FOREIGN KEY (student_id) REFERENCES student (student_id));D
CREATE TABLE student_grades(student_id NUMBER(12),semester_end DATE, gpa NUMBER(4,3), CONSTRAINT student_id_fk FOREIGN KEY (student_id) REFERENCES students (student_id));
考题
单选题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?()A
ALTER TABLE students ADD PRIMARY KEY student_id;B
ALTER TABLE students ADD CONSTRAINT PRIMARY KEY (student_id);C
ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY student_id;D
ALTER TABLE students ADD CONSTRAINT stud_id_pk PRIMARY KEY (student_id);E
ALTER TABLE students MODIFY CONSTRAINT stud_id_pk PRIMARY KEY (student_id);
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