Oracle Database SQL — Question 19

Which three statements are true about indexes and their administration in an Oracle database? (Choose three.)

Answer options

• A. The same table column can be part of a unique and non-unique index.
• B. A descending index is a type of function-based index.
• C. An INVINSIBLE index is not maintained when DML is performed on its underlying table.
• D. If a query filters on an indexed column then it will always be used during execution of the query.
• E. An index can be created as part of a CREATE TABLE statement.
• F. An UNUSABLE index is maintained when DML is performed on its underlying table.

Correct answer: A, B, E

Explanation

The correct answers are A, B, and E because they accurately describe features of indexes in Oracle databases: A states that a column can be part of both index types, B defines a descending index correctly, and E notes that indexes can be created with the table. Options C and F are incorrect because INVISIBLE and UNUSABLE indexes do not behave as described; C incorrectly states that an INVISIBLE index is not maintained, and F incorrectly claims that an UNUSABLE index is maintained.