Lecture 15 Indexed Sequential Access, B trees, Simple prefix B trees Sections 10'1 10'5

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Lecture 15 Indexed Sequential Access,
Btrees,Simple prefix Btrees (Sections 10.1
10.5)
In the Name of God
2
Indexed Sequential Access Btrees, Simple prefix
Btrees

• ????? ??? ??? ???? ??????? ?????? ?? ???? ??? ??
  ???? ???????
• ??????? ??? Indexed Sequential ?????
• ???????????? ISAM ????? ???? ????
• ??? ?????? B-tree ????? ?????? ??? ?? ??????? ??
  ?????? ???? ??????
• ????? ?????? ??? ?? ???????? ?? ???? ?????? ????
  ???? ??????
• ?????? ?? Sequence Set ????? ????
• ???????????? Btree ????? ????
• ???????????? Simple Prefix Btree ????? ????

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Indexed Sequential Access

• ????? ??? ??? ???? ??????? ?????? ?? ????
  ??? ?? ???? ???????
• ??? ?????? ???? ?????? (Indexed Access Method )
• ?????? ?? ???? ?????????? ???? ?? ??????? ??
  ???? ? ??????.
• ??? ?????? ??? (Sequential Access Method )
• ?????? ?? ???? ???????? ???? ?? ????? ???? ????
  ??? ???? ??????? ?? ??????. (????)
• ?? ??????? ???? ???????? ???? ?? ??? ?????? ??
  ??? ???? ???? ???? ??? ?????.
• ?????? ??? ??? ?? ???? ?????? ?? (Batch
  Processing) ?? ?????? ?? ????? ?????? ??? ????
  ???????? ???? ????? ?? ????.
• ???? ?????? ???? ??????? ???????? ?? ??????.

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History ISAM File
???????????? ??? ISAM ????? ???? ????
Prof. Hyoung-Joo Kim, Comp Eng, Seoul National
Univ
5
History ISAM File
???????????? ??? ISAM ????? ???? ????
Example Reorganization
Prof. Hyoung-Joo Kim, Comp Eng, Seoul National
Univ
6
Indexed Sequential Access

• ??? ?????? B-tree ????? ?????? ??? ?? ???????
  ?? ?????? ???? ??????
• ?? ?????? B-tree
• ?????? ???? ??? ???? ?????? ?????? ?????? ??
  ???????? ???? ???????.
• ??????? ????? ???? ???? ???????? ???? ?????
  ??????? ???.
• ?????? ??? ?? ???????? ???? ?????? ???? ????
  ???????. (????)
• ????? ?????? ??? ?? ???????? ?? ???? ??????
  ???? ???? ??????
• ???? ?????? ?? ???? ???? ???? (sort) ???? ?????
  ??? ?? ?????
• ?????? ???? ?? ?? ???? ???????? ?? ???????? ????
  ??? ??????? ????.
• ??? ?????? ????? ?? Sequence Set ??????.

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Indexed Sequential Access

• ?????? ?? Sequence Set ????? ????
• ???????? ???? ?? ?????? ???? ???? ???? ??????.
• ?? ???? ???? ????? ??? ????? ??? ?? ???????
  ??????.
• ???????? ???? ?? ???? ???? ??? (sorted) ??????.
• ???? ?? ??? ?? ????? ?? ?????? ???? ??? ???????.
  
• ??? ????? ???? ?? ??? ?????? ????. ???? ??
  ??????? ??????? ?? ????? ?????.
• ?????? ??? ? ????? ??????? ???? ?????? ?? ??? ???
  B-Tree ???????.
• ????? (insertion) ?? ????? ?? ???? ????? ??? (??
  ???? ?? ???? ??) ???? ??? ???? ????? ??? (Block
  Splitting) ????. (overflow)
• ??? (deletion) ?? ????? ?? ?? ???? ???? ??? ????
  ????? ?? ???? Block Merging ?? Block
  Redistribution ????. (underflow)

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Sequence Set
????
(??? 10.1 ???? 427 ????)
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Sequence Set
???? (?????...)
Prof. Hyoung-Joo Kim, Comp Eng, Seoul National
Univ
10
Sequence Set
???? (?????...)
Prof. Hyoung-Joo Kim, Comp Eng, Seoul National
Univ
11
Sequence Set

• ?????? ?????? sequence set ?????
• ??????? ?? ???? ???? ???? ???????? ???? ???
  ??????? ????? ?? ??? ????? ??? ????.
• ????? ?????? sequence set ?????
• ???? ???? ?????? ???? ??????? ???? ???? ???.
• ??? ???? ?? ?? ?????? 50 ????? ??? ????? ?????
  ?????.
• ????? ?????? ??????? ??? ?? ???? ?? ???? ????
  ??? ?? ?? ?? ????.

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Sequence Set

• ????? ?????? ?????? ?? ???? ????? ????
• ???? ?? ??? Merge / Redistribution ???????
  ?????? ????? RAM ???? ???? ???? ????? 2 ?? 3
  ???? ?? ????? ????.
• ???? ??? ?? ???? ?????? ?? ???? ??? ?? ?????? ??
  ???? (seek) ?????? ????.
• ?? ???? ??? ????? ???? ??? ?????? ?? ???? ???????
  ????? ?? cluster ?????? ???.
• ?? ???? ??? ???? ???? ??? ?????? ?? ???? ?? ?????
  ????? ?? Track ( ?? ??? ?? ) ?????? ???.

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Sequence Set
??? ????? ?????? B-tree ?? ???? ?? ??????
Sequence Set ????? ????
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?????? ?????? BTree

• ???????? ?????? Btree ????? ????
• ?????? ?????? BTree ???? ?? ?????? ?????? ??
  B-Tree ?? ????? ??? ?? ?? ?????
• ?? BTree ???????? ???? ?? ??? ?? ????? reference
  ?? ??? parent ???? ?? ???.
• 2) ???? ????? ???? ?? ??? parent ?? ??? ????? ??
  ????.

Key1 ?????
Key3.
Key1.
Key2.
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Simple Prefix BTree

• ???????? ?????? Simple Prefix Btree ????? ????
• ?? ???? ?? ?????? sequence set ?????? ?? ???????
  ?? separator ??? ????? ??? ?????? ???? ?? ????
  ???? ??.
• Block No. Range of Keys
  Separator
• 1 Adams-Berne
• 2 Bolen-Cage
• 3 Camp-Dutton
• 4 Embry-Evans
• 5 Faber-Folk
• 6 Folks-Gaddis
  

????
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Simple Prefix BTree
???????? ?????? Simple Prefix Btree ????? ????
???? (??? 10.7 ???? 434 ????)
Prof. Hyoung-Joo Kim, Comp Eng, Seoul National
Univ