Chapter 7

Question 1

Does number of tables increases towards higher normalization and number of tables lesser towards denormalization

Answer 1

Yes

Question 2

What is de-normalization

Answer 2

It is not chaos, more like a controlled crash, with the aim of performance enhancement without loss of information.

Question 3

Why we do de-normalization in DSS

Answer 3

Performance

Question 4

Does de-normalization demands more storage space

Answer 4

Yes

Question 5

Do we do time series (collapse time, period) in de-normalization

Answer 5

Yes

Question 6

What is normal form of databases when values are atomic

Answer 6

1NF

Question 7

Does the database size increases in de-normalization

Answer 7

Yes

Question 8

What are 5 techniques of de-normalization

Answer 8

• Adding redundant columns
• Pre-joining
• Splitting table (horizontally or vertically)
• Collapse table
• Derived columns (summary, total)