Because that's exactly what you're asking it to do; every time through the while(), you're setting %IACISBN_ENUM to a hash with a single key.

You want to add keys to it each time, not re-initialize it. Try something more like: 

$IACISBN_ENUM{$IacIsbn} = {
  [...]
};

[download]

In reply to Re: Hash of Hashes not filling - only using last line of file by fullermd
in thread Hash of Hashes not filling - only using last line of file by kdmurphy001

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