13
File Chapter Structures
Brooks/Cole, 2003
OBJECTIVES
After reading this chapter, the reader should be able to:
Understand the file access methods. Describe the characteristics of a sequential file. Describe the characteristics of an indexed file. Describe the characteristics of a hashed file. Distinguish between a text file and a binary file.
Brooks/Cole, 2003
13.1 ACCESS METHODS
Brooks/Cole, 2003
Figure 13-1
Taxonomy of file structures
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13.2 SEQUENTIAL FILES
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Figure 13-2
Sequential file
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Program 13.1 Processing records in a sequential file
While Not EOF { Read the next record Process the record }
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Figure 13-3
Updating a sequential file
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13.3 FILES
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Figure 13-4
Updating process
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Figure 13-5
Mapping in an indexed file
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Figure 13-6
Logical view of an indexed file
Brooks/Cole, 2003
13.4 HASHED FILES
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Figure 13-7
Mapping in a hashed file
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Figure 13-8
Direct hashing
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Figure 13-9
Modulo division
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Figure 13-10
Collision
Brooks/Cole, 200...