As mattr has pointed out, have a look at namazu.org . Their crawler seems also to index pdf pages.
I would recommend you, to try out or read the code of the other search engines mattr provided in his post, before starting writing your own one. You will get a lot of usefull ideas from them.

As for the database, I currently use mysql (unfortunately.., it's slow). I give each word a unique id, and then split the words found in the documents over several tables, so the tables won't get too large.

In reply to Re: Re: Perl Search Applicance by Bluepixel
in thread Perl Search Applicance by PyroX

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