The CUSTOMERS table has these columns:
CUSTOMER_ID NUMBER (4) NOT NULL
CUSTOMER_NAME VARCHAR2 (100) NOT NULL
STREET_ADDRESS VARCHAR2 (150)
CITY_ADDRESS VARHCAR2 (50)
STATE_ADDRESS VARCHAR2 (50)
PROVINCE_ADDRESS VARCHAR2 (50)
COUNTRY_ADDRESS VARCHAR2 (50)
POSTAL_CODE VARCHAR2 (12)
CUSTOMER_PHONE VARCHAR2 (20)
The CUSTOMER_ID column is the primary key for the table.
You need to determine how dispersed your customer base is.
Which expression finds the number of different countries represented in the CUSTOMERS table?（）

单项选择题Evaluate the SQL statement: SELECT ROUND(45.953, -1), TRUNC(45.936, 2) FROM dual; Which values are displayed? （）

A. 46 and 45
B. 46 and 45.93
C. 50 and 45.93
D. 50 and 45.9
E. 45 and 45.93
F. 45.95 and 45.93

单项选择题Which SQL statement accepts user input for the columns to be displayed, the table name, and WHERE condition? （）

A. SELECT &1, "&2" FROM &3 WHERE last_name = '&8';
B. SELECT &1, '&2' FROM &3 WHERE '& last_name = '&8';
C. SELECT &1, &2 FROM &3 WHERE last_name = '&8';
D. SELECT &1, '&2' FROM EMP WHERE last_name = '&8';

多项选择题Which two statements are true about WHERE and HAVING clauses? （）

A. A WHERE clause can be used to restrict both rows and groups.
B. A WHERE clause can be used to restrict rows only.
C. A HAVING clause can be used to restrict both rows and groups.
D. A HAVING clause can be used to restrict groups only.
E. A WHERE clause CANNOT be used in a query of the query uses a HAVING clause.
F. A HAVING clause CANNOT be used in subqueries.

多项选择题Which two statements about creating constraints are true?（）

A. Constraint names must start with SYS_C
B. All constraints must be defines at the column level.
C. Constraints can be created after the table is created.
D. Constraints can be created at the same time the table is created.
E. Information about constraints is found in the VIEW_CONSTRAINTS dictionary view.

单项选择题You are granted the CREATE VIEW privilege. What does this allow you to do? （）

A. Create a table view.
B. Create a view in any schema.
C. Create a view in your schema.
D. Create a sequence view in any schema.
E. Create a view that is accessible by everyone.
F. Create a view only of it is based on tables that you created.