多项选择题X 纠错
A. A main query can have more than one subquery.
B. A subquery can have more than one main query.
C. The subquery and main query must retrieve data from the same table.
D. The subquery and main query can retrieve data from different tables.
E. Only one column or expression can be compared between the subquery and main query.
F. Multiple columns or expression can be compared between the subquery and main query.
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单项选择题
A. Convert any date literal to a date
B. Convert any numeric literal to a date
C. Convert any character literal to a date
D. Convert any date to a character literal
E. Format '10-JAN-99' to 'January 10 1999'
单项选择题
A. The inner query always sorts the results of the outer query
B. The outer query always sorts the results of the inner query
C. The outer query must return a value to the outer query
D. The inner query returns a value to the outer query
E. The inner query must always return a value or the outer query will give an error
单项选择题
A. The start value of the sequence is always 1.
B. A sequence always increments by 1.
C. The minimum value of an ascending sequence defaults to 1.
D. The maximum value of descending sequence defaults to 1.
单项选择题
A. UPDATE employees SET first_name = 'John' SET last_name = 'Smith' WHERE employee_id = 180;
B. UPDATE employees SET first_name = 'John', SET last_name = 'Smoth' WHERE employee_id = 180;
C. UPDATE employee SET first_name = 'John' AND last_name = 'Smith' WHERE employee_id = 180;
D. UPDATE employee SET first_name = 'John', last_name = 'Smith' WHERE employee_id = 180;
单项选择题
A. An error is generated.
B. You will have two identical tables in the HR schema with different names.
C. You create a table called employees in the HR schema based on you EMP table.
D. You create an alternative name for the employees table in the HR schema in your own schema.
单项选择题
A. CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE = SYSDATE);
B. CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE DEFAULT SYSDATE);
C. CREATE OR REPLACE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status VARCHAR2 (10), date_ordered DATE DEFAULT SYSDATE);
D. CREATE OR REPLACE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status NUMBER (10), date_ordered DATE = SYSDATE);
E. CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status NUMBER (10), date_ordered DATE = SYSDATE);
F. CREATE TABLE orders ( order_id NUMBER (10), customer_id NUMBER (8), order_status NUMBER (10), date_ordered DATE DEFAULT SYSDATE);
单项选择题
A. CREATE PUBLIC SYNONYM EDL_VU ON emp_dept_loc_vu
B. CREATE PUBLIC SYNONYM EDL:VU FOR mary (emp_dept_loc_vu);
C. CREATE PUBLIC SYNONYM EDL_VU FOR emp _dept_loc_vu;
D. CREATE SYNONYM EDL_VU ON emp_dept_loc_vu FOR EACH USER;
E. CREATE SYNONYM EDL_VU FOR EACH USER ON emp_dept_loc_vu
F. CREATE PUBLIC SYNONYM EDL_VU ON emp_dept_loc_vu FOR ALL USERS;
多项选择题
A. A single row subquery can retrieve data from only one table.
B. A SQL query statement cannot display data from table B that is referred to in its subquery, unless table B is included in the main query's FROM clause.
C. A SQL query statement can display data from table B that is referred to in its subquery, without including B in its own FROM clause.
D. A single row subquery can retrieve data from more than one table.
E. A single row subquery cannot be used in a condition where the LIKE operator is used for comparison.
F. A multiple-row subquery cannot be used in an INSERT statement to insert multiple rows at a time.
单项选择题
A. INSERT INTO employees (employee_id, first_name, last_name, hire_date) VALUES (1000, 'John', 'smith','01/01/01);
B. INSERT INTO employees(employee_id, first_name, last_name, hire_date) VALUES (1000, 'John', 'smith','01 january 01');
C. INSERT INTO employees(employee_id, first_name, last_name, Hire_date) VALUES (1000, 'John', 'smith', To_ date ('01/01/01));
D. INSERT INTO employees(employee_id, first_name, last_name, hire_date) VALUES (1000, 'John', 'smith','01-Jan-01');