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The ISAM parameter file can accommodate more than one data file. The following data show how a parameter file would look for two data files, each with two index files. Indentation is ignored by the programs, but is helpful in reading the material.
24 4 4 2
0 VENDOR.DAT 384 8192 0 2
2 VENDOR.IDX 14 0 1 1 8192 0 1 32 1
0 10 0
3 6 0 0 0 0 1
12 6 0
1 INVOICE.DAT 192 8192 0 2
4 INVOICE.IDX 16 0 1 1 8192 0 0 0 2
32 6 0
0 6 0
5 10 0 1 1 32 1
0 6 0
The application using this parameter file refers to the vendor data file, VENDOR.DAT, as file number 0, and the invoice data file, INVOICE.DAT, as file number 1. Each data file has two indexes. In both cases, the indexes are stored in one physical file. Except for key number 3, which does not accept duplicates, all the segment lengths sum to 4 bytes less than the actual key lengths to accommodate the suffixes.
