单项选择题
A. completes a transaction on a table
B. modifies the structure and data in a table
C. modifies the data but not the structure of a table
D. modifies the structure but not the data of a table
单项选择题 What does the FORCE option for creating a view do?（）
单项选择题 Examine the structure of the EMPLOYEES table: You need to update the records of employees 103 and 115. The UPDATE statement you specify should update the rows with the values specified below: Which UPDATE statement meets the requirements?（）
单项选择题 Examine the description of the CUSTOMERS table: 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) The CUSTOMER_ID column is the primary key for the table. Which statement returns the city address and the number of customers in the cities Los Angeles or San Francisco?（）