IBM DB2 11.1 Advanced DBA for Linux, UNIX, and Windows — Question 3

Shadow tables are a special kind of Materialized Query Table, but what makes them different? (Choose two.)

Answer options

• A. Shadow tables cannot be queried directly
• B. Shadow tables do not store their data on disk
• C. Shadow tables must be organized by column
• D. Shadow tables must be maintained by replication
• E. You cannot join shadow tables to other kinds of tables CD

Correct answer:

Explanation

The correct answers are A and B. Shadow tables cannot be queried directly, meaning that users cannot perform SQL queries on them. Additionally, shadow tables do not store data on disk, as they are intended to function in-memory. The other options are incorrect because shadow tables do not have specific organization requirements by column, they can be maintained in various ways, and they can be joined with other tables under certain conditions.