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Figure:

Computer Sciencean overview

EDITION 7

J. Glenn Brookshear

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C H A P T E R 8

File Structures

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Figure 8.1: The role of an operating system when accessing a file

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Figure 8.2: Maintaining a file’s order by means of a file allocation table

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Figure 8.3: A procedure for merging two sequential files

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Figure 8.4: Applying the merge algorithm (Letters are used to represent entire records. The particular letter indicates the value of the record’s key field.) (continued)

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Figure 8.4: Applying the merge algorithm (Letters are used to represent entire records. The particular letter indicates the value of the record’s key field.)

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Figure 8.5: The structure of a simple employee file implemented as a text file

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Figure 8.6: The first two bars of Beethoven’s Fifth Symphony

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Figure 8.7: Converting data from two’s complement notation into ASCII for storage in a text file (continued)

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Figure 8.7: Converting data from two’s complement notation into ASCII for storage in a text file

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Figure 8.8: Opening an indexed file

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Figure 8.9: An inverted file

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Figure 8.10: A file with a partial index

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Figure 8.11: The rudiments of a hashing system, in which each bucket holds those records that hash to that bucket number (continued)

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Figure 8.11: The rudiments of a hashing system, in which each bucket holds those records that hash to that bucket number

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Figure 8.12: Hashing the key field value 25X3Zto one of 40 buckets

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Figure 8.13: Handling bucket overflow

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Figure 8.14: A large file partitioned into bucketsto be accessed by hashing