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The ISAM parameter file is composed of five types of records:
Each parameter file begins with one Initialization Record which specifies, among other things, the number of data files. Then for each data file there are a group of records beginning with a Data File Description record. Each Data File Description record specifies the number of indexes it uses. For each of these indexes there is a group of records beginning with the Index File Description record or Index Member record. Each Index File Description record and/or optional Index Member record is followed by one or more Key Segment Description records.
The overall organization of the records is shown in the following schematic and reflects the hierarchical relationship among the data files and their corresponding indexes:
Parameter File Organization
Initialization Record
Data File Description Record
First Index File Description Record
First Key Segment Description Record
:::
Last Key Segment Record
Optional Index Member Records
First Key Segment Description Record
:::
Last Key Segment Record
:::
Last Index File or Index Member Record
First Key Segment Description Record
:::
Last Key Segment Record
REPEAT FOR EACH DATA FILE
