A. noneB. DELETE, INSERT,SELECTC. ALTER, DELETE, INSERT……

多项选择题Examine the structure of the EMPLOYEES table: EMPLOYEE_ID NUMBER NOT NULL, Primary Key EMP_NAME VARCHAR2(30) JOB_ID NUMBER SAL NUMBER MGR_ID NUMBER References EMPLOYEE_ID column DEPARTMENT_ID NUMBER Foreign key to DEPARTMENT_ID column of the DEPARTMENTS table You created a sequence called EMP_ID_SEQ in orderto populate sequential values for the EMPLOYEE_ID column of the EMPLOYEES table. Which two statements regarding the EMP_ID_SEQ sequence are true? （）

A. You cannot use the EMP_ID_SEQ sequence to populate the JOB_ID column.
B. The EMP_ID_SEQ sequence is invalidated when you modify the EMPLOYEE_ID column.
C. The EMP_ID_SEQ sequence is not affected by modifications to the EMPLOYEES table.
D. Any other column of NUMBER data type in your schema can use the EMP_ID_SEQ sequence.
E. The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEES table.
F. The EMP_ID_SEQ sequence is dropped automatically when you drop the EMPLOYEE_ID column.

单项选择题What is true about joining tables through an equijoin?（）

A. You can join a maximum of two tables through an equijoin.
B. You can join a maximum of two columns through an equijoin.
C. You specify an equijoin condition in the SELECT or FROM clauses of a SELECT statement.
D. To join two tables through an equijoin, the columns in the join condition must be primary key and foreign key columns.
E. You can join n tables (all having single column primary keys) in a SQL statement by specifying a minimum of n-1 join conditions.

多项选择题Which four are types of functions available in SQL? （）

A. string
B. character
C. integer
D. calendar
E. numeric
F. translation
G. date
H. conversion

单项选择题You need to calculate the total of all salaries in the accounting department. Which group function should you use?（）

A. MAX
B. MIN
C. SUM
D. COUNT
E. TOTAL
F. LARGEST

单项选择题You define a multiple-row subquery in the WHERE clause of an SQL query with a comparison operator = .What happens when the main query is executed?（）

A. The main query executes with the first value returned by the subquery.
B. The main query executes with the last value returned by the subquery.
C. The main query executes with all the values returned by the subquery.
D. The main query fails because the multiple-row subquery cannot be used with the comparison operator.
E. You cannot define a multiple-row subquery in the WHERE clause of a SQL query.