Sequential File Organization

1
Sequential File Organization

• ?????? ???????
• ??????????????????????????
• ?????????????? ????????????????????????

2
???????

• ????????????????????????????????????
• ???????????????????????????
• ???????????????????????????
• ???????????????????????????
• ?????????????????????????????????
• ????????????????????

3
????????????

• ????????????????????????? ??????????????????
• ??????????????????????????????????
• ??????????????????????????????????????????????????
  ?
• ??????????????????? Record 10 ?????????? Record
  1, 2, ..., 9
• ?????????????????? ???????????????????????????????
  ???????
• ????????????????? Tape , Disk

4
??????????????????

• Order File ????????????????????? Record
  ???????????? Primary Key ???
• ?????? Primary key ??? i ???????????? Primary
  key ??? j
• Pile File ????????????????????????????????????????
  ?? ??????? Record ?????????????????????

5
????????????? ???????????????????

• ?? 1 File ????????????????????????????? ????
  Transaction File ???????????????????? ???????????
  ????????????????? ???????????????????????????????
  1 Field ???????????????????????????????????
• ???????????????? Record ????? ?????????????????
  ????????? ?????????? Record ?????????
  ????????????????? ???? ???? Record 50 ???????????
  Record 10

6
?????????????????

• ????????? Record ?????????????????????????????????
  ????
• ?????????????????????
• Master File
• Transaction File
• Report File

7
??????????????????????????(Transaction File)

• ??????????????? ??????????????????????????????????
  ????????
• ??????????????????????????????
• ??????????????????????????????????????????????????
  
• ??????????????????????????????????????????????????
  ????????????? ???????????????????????????????????
  ???? ?????????????????

8
??????????????????????????

• ???????????????
• ????????????????? Key

Transaction File
Sorting process
Sorted Transaction File
9
????????????????????????????

• ??????????????????????????????
• ?????????????
• ???????????????
• ????????????????????????

10
??????????????????? (Data Entry Device)

• key-to-card
• key-to-tape
• key-to-disk
• keyboard

• optical scanner
• bar code reader
• magnetic reader

11
??????????????????????

• ?????????????????????????????????????????????
• ????????????????????????? ??????????????????

12
??????????????????

• ????????????????????????????????
• ????? ???????? ????????
• ???????????????
• ??????
• ?????????? 3 ????????
• Header
• Detail
• Footer

13
??????????? Record ???????????

• Record ???????????????????????????????????????????
  ???????????????????????????????????????
• ??????????????????????????????????????????????????
  ?? ?????????????? ?????? Report generator
• ???????????????????????
• ???????????????????????????????????????? Record
  (Inquiry)

14
????????????????????

• ?????????????? (Mater File) ?????????????????????
• ??????????????????????????????? ???? ??????????
  ??????????
• ??????????????????? Master File ??????????????
• ??????????? Master File ?????????????? Batch
  Processing
• ??????????? Transaction ???????? ???????? Master
  File

15
????????????????????? ?????????

• ????????????????????????? Master File ????????
  Version ??????????????????? Recovery ??????
  ????????????????????????????????? ??????????????

16
??????????????????? ?????????????? ????????
?????????????? ??????????

• 1. get-next-old-master( read eof)
• 2. get-next-transactions( read eof)
• 3. until end-of-old-master or end-of-transactions
  do
• if trans-key gt old-master-key then
• no trans
• copy old-master-to-new-master
• get-next-old-master
• else
• if trans-key old-master-key then
• make change in master record
• output master record to new master
• get-next-old-master
• get-next-transactions
• else
• if trans-key lt old-master-key then
• display no record in master to update
• get-next-transactions
• endif
• endif

17
??????????????????? ????????? ???????? lt
????????? ??????????

• ?????? 3.7 1. get-next-old-master( read eof)
• 2. get-next-transactions( read eof)
• 3. until end-of-old-master or end-of-transactions
  do
• if trans-key gt old-master-key then
• no trans for update
• get-next-old-master
• else
• if trans-key old-master-key then
• make change in master record
• get-next-transactions
• else
• if trans-key lt old-master-key then
• display no record in master to update
• get-next-transactions
• endif
• endif
• endif
• enduntil

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?????? ???????????????????????????????????

• ????????????????????????????
• ??????????????
• ?????????????????????????????????
• File Activity Ratio Record ?????????? MF /
  Record ?? MF
• ?????? ??????????????????????? Interactive
  ??????????????????????

19
????????????????????????????

• ???????? Record ?????????????????????(Insert
  Record)
• ????? Record ???????????????????(Delete Record)
• ??????????????????????????????? Record (Update
  Record)

20
??????????????????????????????????

• ????? Record ?????????????????
• ?? Record ??????????????
• ??????????? Record ??????????????

21
??????????????????

• ??????? Record ?????????? ????????? (field)
  ????????
• ????????? Record
• Fixed Length record
• Variable length record , Repeat group field
• ?????????????????? Primary Key
• Blocking Factor ?????????????????????????

22
??????? Record ??? Field

• Activity Field
• Inactivity Filed
• Activity Record
• Inactivity Record

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?????????? Primary Key

• ??????????????????????
• ??????? Transaction File ??? field ???????? Mater
  File
• ??????????????????????????? ??????????????????????
  ????????
• ??????? Master File ????????? Unique
  ???????????????????????????????????????????
  Record ???

24
??????? Blocking Factor

• Tape gt ??????? Blocking Factor
  ?????????????????????????????? ???????????????????
  ???? Buffer ?????????????
• Disk gt ????????????????????????? Cluster
  (sector , Track) ??????????????????? Buffer
  ?????????????

25
??????????????????????

• ???????????????????????
• ???????????????????????????
• ?????????????????? ???????????????????????????
• ????????????????????????? ????????????????????????
  ?????????????
• ???????????????????? ?????????????????????????????
  ?? ?????????????????????????????????????
• ???????????????????????????? ?????????????????????
  ???????????????????? ???? ??????????????

26
????????????????????

• ???????????????????????????????
• ??????????????????????????????????????????????????
  ?????????? ???? inquiry ???? interactive
  transaction processing

27
????????????????????

• IDENTIFICATION DIVISION
• ENVIRONMENT DIVISION
• SELECT OLD-MASTER ASSIGN TO TAPE.
• FD OLD-MASTER
• LABEL RECORDS ARE STANDARD
• RECORD CONTAINS 100 CHARACTERS
• BLOCK CONTAINS 20 RECORDS
• DATA RECORD IS OLD-MASTER-REC.
• ORGANIZATION IS SEQUENTIAL.
• ACCESS MODE IS SEQUENTIAL.
• 3. DATA DIVISION
• 01 old-master-record.
• 05 student-no picture 9(7).
• 05 student-name picture A(30).
• 05 student-address picture X(30).
  
• 4. PROCEDURE DIVISION