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单选题
Examine the description of the MARKS table: STD_ID NUMBER(4) STUDENT_NAME VARCHAR2(30) SUBJ1 NUMBER(3) SUBJ2 NUMBER(3) SUBJ1 and SUBJ2 indicate the marks obtained by a student in two subjects. Examine this SELECT statement based on the MARKS table: SELECT subj1+subj2 total_marks, std_id FROM marks WHERE subj1 > AVG(subj1) AND subj2 > AVG(subj2) ORDER BY total_ marks; What is the result of the SELECT statement?()
A

The statement executes successfully and returns the student ID and sum of all marks for each student who obtained more than the average mark in each subject.

B

The statement returns an error at the SELECT clause.

C

The statement returns an error at the WHERE clause.

D

The statement returns an error at the ORDER BY clause.


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考题 Examine the description of the MARKS table:SUBJ1 and SUBJ2 indicate the marks obtained by a student in two subjects.Examine this SELECT statement based on the MARKS table:What is the result of the SELECT statement?()A. The statement executes successfully and returns the student ID and sum of all marks for each student who obtained more than the average mark in each subject.B. The statement returns an error at the SELECT clause.C. The statement returns an error at the WHERE clause.D. The statement returns an error at the ORDER BY clause.

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考题 多选题Examine the command that is used to create a table: SQL CREATE TABLE orders(oid NUMBER(6) PRIMARY KEY, odate DATE, ccode NUMBER (6), oamtNUMBER(10,2)) TABLESPACE users; Which two statements are true about the effect of the above command()AA CHECK constraint is created on the OID column.BA NOT NULL constraint is created on the OID column.CThe ORDERS table is the only object created in the USERS tablespace.DThe ORDERS table and a unique index are created in the USERS tablespace.EThe ORDERS table is created in the USERS tablespace and a unique index is created on the OID columnin the SYSTEM tablespace.

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考题 多选题Examine the description of the STUDENTS table: STD_ID NUMBER(4) COURSE_ID VARCHAR2(10) START_DATE DATE END_DATE DATE Which two aggregate functions are valid on the START_DATE column? ( )ASUM(start_date)BAVG(start_date)CCOUNT(start_date)DAVG(start_date,end_date)EMIN(start_date)FMAXIMUM(start_date)

考题 多选题Examine the description of the MARKS table: STD_ID NUMBER(4) STUDENT_NAME VARCHAR2(30) SUBJ1 NUMBER(3) SUBJ2 NUMBER(3) SUBJ3 NUMBER(3) SUBJ1, SUBJ2, and SUBJ3 indicate the marks (grades) obtained by a student in the three subjects. Which two statements are valid? ()ASELECT SUM(subj1, subj2, subj3) FROM marks;BSELECT SUM(subj1 + subj2 + subj3) FROM marks;CSELECT SUM(subj1), SUM(subj2), SUM(subj3) FROM marks;DSELECT MAX(subj1, subj2, subj3) FROM marks;ESELECT MINIMUM(subj1) FROM marks;FSELECT COUNT(std_id) FROM marks WHERE subj1 = AVG(subj1);

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考题 单选题Which SQL statement defines the FOREIGN KEY constraint on the DEPTNO column of the EMP table?()A CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) NOT NULL CONSTRAINT emp_deptno_fk FOREIGN KEY deptno REFERENCES dept deptno);B CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) CONSTRAINT emp_deptno_fk REFERENCES dept (deptno));C CREATE TABLE EMP (empno NUMBER(4) ename VARCHAR2(35), deptno NUMBER(7,2) NOT NULL, CONSTRAINT emp_deptno_fk REFERENCES dept (deptno) FOREIGN KEY (deptno));D CREATE TABLE EMP (empno NUMBER(4), ename VARCNAR2(35), deptno NUMBER(7,2) FOREIGN KEY CONSTRAINT emp deptno fk REFERENCES dept (deptno));