Oracle Database 12c: Installation and Administration — Question 37

Which two statements are true about extents? (Choose two.)

Answer options

• A. Blocks belonging to an extent can be spread across multiple data files.
• B. Data blocks in an extent are logically contiguous but can be non-contiguous on disk.
• C. The blocks of a newly allocated extent, although free, may have been used before.
• D. Data blocks in an extent are automatically reclaimed for use by other objects in a tablespace when all the rows in a table are deleted.

Correct answer: B, C

Explanation

Option B is correct because it highlights that the data blocks are logically contiguous, even if they are not physically adjacent on disk. Option C is also correct as it indicates that newly allocated extent blocks can be free but previously used. Options A and D are incorrect because option A inaccurately suggests that blocks in one extent can be in multiple data files, and option D misstates the automatic reclamation process of blocks in extents.