 | Programmer's Guide (9.1 revision 1) |  |
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You must supply the logical record length to the Create operation (14). The logical record length is the number of bytes of fixed-length data in the file. To obtain this value, calculate how many bytes of data you need to store in the fixed-length portion of each record.
For example, the following table shows how the data bytes in the example Employees file are added together to obtain a logical record length:
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Field
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Length (in Bytes)
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Last Name
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25
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First Name
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25
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Middle Initial
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1
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Employee ID
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4
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Phone Number
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13
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Pay Rate
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4
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LOGICAL RECORD LENGTH
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72
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In calculating the logical record length, you do not count variable-length data, because variable-length information is stored apart from the fixed-length record in the file (on variable pages, not data pages).
Note
The maximum logical record length is (page size - 8 - record overhead) for 8.x files and (page size - 6 - record overhead) otherwise, except for files with a variable-record length. The maximum record length is practically unlimited for files with a variable-record length.
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Chapter contents
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