You have run into Autovivification.

To avoid that, you can do something like: 

 for( grep {exists $CATEGORY_DATA{$_}} 1..10){
   if( $FD_NAME eq $CATEGORY_DATA{$_}{FIELD_NAME}) { 
    ...
   }
  }

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     "As you get older three things happen. The first is your memory goes, and I can't remember the other two... " - Sir Norman Wisdom

In reply to Re: Automatic creation of hash elements by NetWallah
in thread Automatic creation of hash elements by atemon

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