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.

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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.

多项选择题Evaluate the SQL statement DROP TABLE DEPT: Which four statements are true of the SQL statement? （）

A. You cannot roll back this statement.
B. All pending transactions are committed.
C. All views based on the DEPT table are deleted.
D. All indexes based on the DEPT table are dropped.
E. All data in the table is deleted, and the table structure is also deleted.
F. All data in the table is deleted, but the structure of the table is retained.
G. All synonyms based on the DEPT table are deleted.

单项选择题Which statement describes the ROWID data type? （）

A. Binary data up to 4 gigabytes.
B. Character data up to 4 gigabytes.
C. Raw binary data of variable length up to 2 gigabytes.
D. Binary data stored in an external file, up to 4 gigabytes.
E. A hexadecimal string representing the unique address of a row in its table.

单项选择题You need to produce a report for mailing labels for all customers. The mailing label must have only the customer name and address. The CUSTOMERS table has these columns: CUST_ID NUMBER(4) NOT NULL CUST_NAME VARCHAR2(100) NOT NULL CUST_ADDRESS VARCHAR2(150) CUST_PHONE VARCHAR2(20) Which SELECT statement accomplishes this task?（）

A. SELECT* FROM customers;
B. SELECT name, address FROM customers;
C. SELECT id, name, address, phone FROM customers;
D. SELECT cust_name, cust_address FROM customers;
E. SELECT cust_id, cust_name, cust_address, cust_phone FROM customers;