问题：多选题Which two statements are true about constraints? （）AThe UNIQUE constraint does not permit a null value for the column.BA UNIQUE index gets created for columns with PRIMARY KEY and UNIQUE constraints.CThe PRIMARY KEY and FOREIGN KEY constraints create a UNIQUE index.DThe NOT NULL constraint ensures that null values are not permitted for the column.
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问题：单选题The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) Which statement finds the rows in the CUSTOMERS table that do not have a postal code?（）A SELECT customer_id, customer_name FROM customers WHERE postal_code CONTAINS NULL;B SELECT customer_id, customer_name FROM customers WHER postal_code = ' ___________';C SELECT customer_id, customer_name FROM customers WHERE postal _ code IS NULL;D SELECT customer_id, customer_name FROM customers WHERE postal code IS NVL;E SELECT customer_id, customer_name FROM customers WHERE postal_code = NULL;
问题：单选题The CUSTOMERS table has these columns: CUSTOMER_ID NUMBER(4) NOT NULL CUSTOMER_NAME VARCHAR2(100) NOT NULL STREET_ADDRESS VARCHAR2(150) CITY_ADDRESS VARCHAR2(50) STATE_ADDRESS VARCHAR2(50) PROVINCE_ADDRESS VARCHAR2(50) COUNTRY_ADDRESS VARCHAR2(50) POSTAL_CODE VARCHAR2(12) CUSTOMER_PHONE VARCHAR2(20) A promotional sale is being advertised to the customers in France. Which WHERE clause identifies customers that are located in France?（）A WHERE lower(country_address) = franceB WHERE lower(country_address) = 'france'C WHERE lower(country_address) IS 'france'D WHERE lower(country_address) = '%france%'E WHERE lower(country_address) LIKE %france%
问题：多选题Which are /SQL*Plus commands? （）AINSERTBUPDATECSELECTDDESCRIBEEDELETEFRENAME
问题：单选题Evaluate the SQL statement: SELECT ROUND(TRUNC(MOD(1600,10),-1),2) FROM dual; What will be displayed?（）A 0B 1C 0.00D An error statement
问题：多选题Which three statements inserts a row into the table?（）AINSERT INTO employees VALUES ( NULL, ‘John’,‘Smith’);BINSERT INTO employees( first_name, last_name) VALUES(‘John’,‘Smith’);CINSERT INTO employees VALUES (‘1000’,‘John’,NULL);DINSERT INTO employees(first_name,last_name, employee_id) VALUES ( 1000, ‘John’,‘Smith’);EINSERT INTO employees (employee_id) VALUES (1000);FINSERT INTO employees (employee_id, first_name, last_name) VALUES ( 1000, ‘John’,‘’);
问题：单选题Evaluate the SQL statement:SELECT ROUND(45.953, -1), TRUNC(45.936, 2)FROM dual;Which values are displayed?（）A 46 and 45B 46 and 45.93C 50 and 45.93D 50 and 45.9E 45 and 45.93F 45.95 and 45.93
问题：多选题Evaluate the SQL statement DROP TABLE DEPT: Which four statements are true of the SQL statement? （）AYou cannot roll back this statement.BAll pending transactions are committed.CAll views based on the DEPT table are deleted.DAll indexes based on the DEPT table are dropped.EAll data in the table is deleted, and the table structure is also deleted.FAll data in the table is deleted, but the structure of the table is retained.GAll synonyms based on the DEPT table are deleted.
问题：单选题You own a table called EMPLOYEES with this table structure: EMPLOYEE_ID NUMBER Primary Key FIRST_NAME VARCHAR2(25) LAST_NAME VARCHAR2(25) HIRE_DATE DATE What happens when you execute this DELETE statement? DELETE employees; （）A You get an error because of a primary key violation.B The data and structure of the EMPLOYEES table are deleted.C The data in the EMPLOYEES table is deleted but not the structure.D You get an error because the statement is not syntactically correct.
问题：单选题You need to perform certain data manipulation operations through a view called EMP_DEPT_VU, which you previously created. You want to look at the definition of the view (the SELECT statement on which the view was created.) How do you obtain the definition of the view?（）A Use the DESCRIBE command on the EMP_DEPT_VU view.B Use the DEFINE VIEW command on the EMP_DEPT_VU view.C Use the DESCRIBE VIEW command on the EMP_DEPT_VU view.D Query the USER_VIEWS data dictionary view to search for the EMP_DEPT_VU view.E Query the USER_SOURCE data dictionary view to search for the EMP_DEPT_VU view.F Query the USER_OBJECTS data dictionary view to search for the EMP_DEPT_VU view.
问题：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));
问题：多选题Which three are DATETIME data types that can be used when specifying column definitions? （）ATIMESTAMPBINTERVAL MONTH TO DAYCINTERVAL DAY TO SECONDDINTERVAL YEAR TO MONTHETIMESTAMP WITH DATABASE TIMEZONE
问题：单选题Evaluate the SQL statement: 1 SELECT a.emp_name, a.sal, a.dept_id, b.maxsal 2 FROM employees a, 3 (SELECT dept_id, MAX(sal) maxsal 4. FROM employees 5 GROUP BY dept_id) b 6 WHERE a.dept_id = b.dept_id 7 AND a. asl < b. maxsal; What is the result of the statement?（）A The statement produces an error at line 1.B The statement produces an error at line 3.C The statement produces an error at line 6.D The statement returns the employee name, salary, department ID, and maximum salary earned in the department of the employee for all departments that pay less salary then the maximum salary paid in the company.E The statement returns the employee name, salary, department ID, and maximum salary earned in the department of the employee for all employees who earn less than the maximum salary in their department.
问题：多选题Which four are types of functions available in SQL? （）AstringBcharacterCintegerDcalendarEnumericFtranslationGdateHconversion
问题：单选题Evaluate these two SQL statements: SELECT last_name, salary , hire_date FROM EMPLOYEES ORDER BY salary DESC; SELECT last_name, salary , hire_date FROM EMPLOYEESORDER BY 2 DESC; What is true about them?（）A The two statements produce identical results.B The second statement returns a syntax error.C There is no need to specify DESC because the results are sorted in descending order by default.D The two statements can be made to produce identical results by adding a column alias for the salary column in the second SQL statement.
问题：多选题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? （）ASER_NOBORDER_IDCSTATUSDPROD_IDEORD_TOTALFComposite index on ORDER_ID and ORDER_DATE
问题：单选题Which describes the default behavior when you create a table? （）A The table is accessible to all users.B Tables are created in the public schema.C Tables are created in your schema.D Tables are created in the DBA schema.E You must specify the schema when the table is created.
问题：多选题Which four are correct guidelines for naming database tables? （）AMust begin with either a number or a letter.BMust be 1-30 characters long.CShould not be an Oracle Server reserved word.DMust contain only A-Z, a-z, 0-+, _, *, and #.EMust contain only A-Z, a-z, 0-9, _, $, and #.FMust begin with a letter.
问题：单选题What does the TRUNCATE statement do?（）A Removes the tableB Removes all rows from a tableC Shortens the table to 10 rowsD Removes all columns from a tableE Removes foreign keys from a table
问题：多选题Which three statements about subqueries are true?（）AA single row subquery can retrieve only one column and one row.BA single row subquery can retrieve only one row but many columns.CA multiple row subquery can retrieve multiple rows and multiple columns.DA multiple row subquery can be compared by using the “>” operator.EA single row subquery can use the IN operator.FA multiple row subquery can use the “=” operator.
