多选题Examine the description of the STUDENTS table: STD_ID NUMBER(4) COURSE_ID VARCHARD2(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,

第1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';

第2题：

Which two are true about aggregate functions? （）

• A、You can use aggregate functions in any clause of a SELECT statement.
• B、You can use aggregate functions only in the column list of the select clause and in the WHERE clause of a SELECT statement.
• C、You can mix single row columns with aggregate functions in the column list of a SELECT statement by grouping on the single row columns.
• D、You can pass column names, expressions, constants, or functions as parameter to an aggregate function.
• E、You can use aggregate functions on a table, only by grouping the whole table as one single group.
• F、You cannot group the rows of a table by more than one column while using aggregate functions.

第3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）， oamt NUMBER（10，2）） TABLESPACE users；  Which two statements are true about the effect of the above command） （）

• A、A CHECK constraint is created on the OID column.
• B、A NOT NULL constraint is created on the OID column.
• C、The ORDERS table is the only object created in the USERS tablespace.
• D、The ORDERS table and a unique index are created in the USERS tablespace.
• E、The ORDERS table is created in the USERS tablespace and a unique index is created on the OIDcolumn in the SYSTEM tablespace.

第4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';

第5题：

You need to create a table named ORDERS that contain four columns: 1. an ORDER_ID column of number data type 2. aCUSTOMER_ID column of number data type 3. an ORDER_STATUS column that contains a character data type 4. aDATE_ORDERED column to contain the date the order was placed. When a row is inserted into the table, if no value is provided when the order was placed, today's date should be used instead. Which statement accomplishes this?（）

• A、CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE = SYSDATE);
• B、CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE DEFAULT SYSDATE);
• C、CREATE OR REPLACE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE DEFAULT SYSDATE);
• D、CREATE OR REPLACE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE = SYSDATE);
• E、CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status NUMBER (10), date_ordered DATE = SYSDATE);
• F、CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status NUMBER (10), date_ordered DATE DEFAULT SYSDATE);

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第10题：

Examine the description of the STUDENTS table: STD_ID NUMBER(4) COURSE_ID VARCHARD2(10) START_DATE DATE END_DATE DATE Which two aggregate functions are valid on the START_DATE column?（）

• A、SUM(start_date)
• B、AVG(start_date)
• C、COUNT(start_date)
• D、AVG(start_date, end_date)
• E、MIN(start_date)
• F、MAXIMUM(start_date)

第11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));

第12题：

Examine the SQL statements that creates ORDERS table: CREATE TABLE orders (SER_NO NUMBER UNIQUE, ORDER_ID NUMBER, ORDER_DATE DATE NOT NULL STATUS VARCHARD2(10) CHECK (status IN ('CREDIT','CASH')), PROD_ID_NUMBER REFERENCES PRODUCTS(PRODUCT_ID), ORD_TOTAL NUMBER, PRIMARY KEY (order id, order date)); For which columns would an index be automatically created when you execute the aboveSQL statement? （）

• A、SER_NO
• B、ORDER_ID
• C、STATUS
• D、PROD_ID
• E、ORD_TOTAL
• F、Composite index on ORDER_ID and ORDER_DATE

第13题：

You need to create a table named ORDERS that contains four columns: 1.an ORDER_ID column of number data type 2.a CUSTOMER_ID column of number data type 3.an ORDER_STATUS column that contains a character data type 4.a DATE_ORDERED column to contain the date the order was placed When a row is inserted into the table, if no value is provided for the status of the order, the value PENDING should be used instead. Which statement accomplishes this?（）

• A、CREATE TABLE orders ( order_id NUMBER(10), customer_id NUMBER(8), order_status NUMBER(10) DEFAULT 'PENDING', date_ordered DATE );
• B、CREATE TABLE orders ( order_id NUMBER(10), customer_id NUMBER(8), order_status VARCHAR2(10) = 'PENDING', date_ordered DATE );
• C、CREATE OR REPLACE TABLE orders ( order_id NUMBER(10), customer_id NUMBER(8), order_status VARCHAR2(10) DEFAULT 'PENDING', date_ordered DATE );
• D、CREATE OR REPLACE TABLE orders ( order_id NUMBER(10), customer_id NUMBER(8), order_status VARCHAR2(10) = 'PENDING', date_ordered DATE );
• E、CREATE TABLE orders ( order_id NUMBER(10), customer_id NUMBER(8), order_status VARCHAR2(10) DEFAULT 'PENDING', date_ordered DATE );
• F、CREATE TABLE orders ( order_id NUMBER(10), customer_id NUMBER(8), order_status VARCHAR2(10) DEFAULT 'PENDING', date_ordered VARCHAR2 );

第14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? （　）

• A、SUM（start_date）
• B、AVG（start_date）
• C、COUNT（start_date）
• D、AVG（start_date，end_date）
• E、MIN（start_date）
• F、MAXIMUM（start_date）

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