单项选择题
A. Group functions on columns ignore NULL values.
B. Group functions on columns returning dates include NULL values.
C. Group functions on columns returning numbers include NULL values.
D. Group functions on columns cannot be accurately used on columns that contain NULL values.
E. Group functions on columns include NULL values in calculations if you use the keyword INC_NULLS.
多项选择题 Examine the SQL statement that creates ORDERS table: CREATE TABLE orders (SER_NO NUMBER UNIQUE, ORDER_ID NUMBER, ORDER_DATE DATE NOT NULL, STATUS VARCHAR2(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 above SQL statement? ()
单项选择题 Which object privileges can be granted on a view?()
单项选择题 Which SQL statement generates the alias Annual Salary for the calculated column SALARY*12?()