The key length must be a numeric constant between 1 and the record length.
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Cause . . . . . : The key length must be a numeric constant with zero decimal positions between 1 and the record length of the file. If the key length is a named constant or built-in function, it must be fully defined before the file declaration. The key length defaults to 1.
Recovery . . . : Correct the key length. Compile again.