Did I miss-apply what you were trying to say?

Yes.

Change "ok" to {}, and that should work. 

while ($book_id = $sth->fetchrow_array()) {
     $booklist_1{$book_id} = {};
}

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Even then, I urge you to Use strict and warnings. It would have saved you from creating this problem in the first place. Instead of silently doing what you didn't want, it would have told you on its death bed, 

Can't use string ("1") as a HASH ref while "strict refs" in use

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It's not the best error message in this case, but it would have served better than the mystery you had. If you'd not been able to figure it out, you could have posted it here, and we would have been able to answer immediately rather than groping around.

So I say a third time, Use strict and warnings

In reply to Re^5: Why is my code assigning the last-retrieved value to all elements in my hash? by kyle
in thread Why is my code assigning the last-retrieved value to all elements in my hash? by punch_card_don

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