单项选择题

A. Exhibit AB. Exhibit B C. The query returns no rows D……

EXHIBIT, Emp Table

Exhibit A

Exhibit B

Examine the data from the EMP table.
Evaluate this SQL statement:
SELECT *
FROM emp
WHERE emp _ id = 3);
WHERE commission = (SELECT commission
FROM emp
What is the result when the query is executed?（）

A. Exhibit A
B. Exhibit B
C. The query returns no rows
D. The query fails because the outer query is retrieving more than one column
E. The query fails because both the inner and outer queries are retrieving data from the same table.

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热门试题

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For which action can you use the TO_DATE function?（）

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What is true regarding subqueries?（）

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.