01 Storage

Question 1

Slotted Pages

Answer 1

• Slot Stores Offset + size
• Tuple data stored from back to front

Question 2

Slotted Pages Variant

Answer 2

• fixed-length data stored directly in slots

Question 3

What are record ids?

Answer 3

Tuple of
- unique page-id
- slot number

Question 4

Row Store

Answer 4

All attributes of a Tuple are stored in one page

Question 5

Column store

Answer 5

Different pages for individual columns of a table

Question 6

What is the buffer pool?

Answer 6

Cache of data in main memory

Question 7

2 Eviction Strategies

Answer 7

• FIFO
• LRU

Question 8

Efficient Approximation of LRU

Answer 8

• Clock Algorithm

Question 9

How does Clock work?

Answer 9

• set reference=1 if page is requested
  If page needs to be evicted:
  1. check frame
  2. if ref=1 set it to 0 and go to next frame, goto 1
  3. else evict page in frame