Q5. Which two statements are true about table data storage in an Oracle database?
- A) Multiple row pieces from the same row must be stored in different database blocks.
- B) Index block free space is always contiguous in the middle of the block.
- C) Data block free space is always contiguous in the middle of the block.
- D) A table row can be chained across several database blocks.
- E) Multiple row pieces from the same row may be stored in different database blocks.
Answer: D,E
Explanation:
https://docs.oracle.com/en/database/oracle/oracle-database/19/cncpt/logical-storage-structures.html#GUID-49D4E586-57BF-4310-9EE9-2DD54108E651
In row chaining, Oracle Database stores the data for the row in a chain of one or more data blocks reserved for the segment. Row chaining most often occurs with large rows. Examples include rows that contain a column of data type LONG or LONG RAW, or a row with a huge number of columns. Row chaining in these cases is unavoidable. Answer D
Oracle Database can only store 255 columns in a row piece. Thus, if you insert a row into a table that has 1000 columns, then the database creates 4 row pieces, typically chained over multiple blocks. Answer E