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All the Perl that's Practical to Extract and Report
I pour the blue liquid on the red liquid. If it doesn't blow up on my
face, I proceed to turn up the flame under the blue liquid, and so on.
I have very little idea of what I am really doing, I just like the
pretty colors :-)
-- Jarkko Hietaniemi
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How beefy is the database? (Score:1)
Can we assume that it is capable of doing a join like this?
SELECT with1.page_id
, with1.number_of_occurrences
FROM reverse_index with1
LEFT JOIN reverse_index without1
ON with1.word_id = ?
AND without1.word_id = ?
AND with1.page_id = without1.page_id
WHERE without1.page_id IS NULL
ORDER BY with1.number_of_occurrences DESC
If we are forced to assume that this can't work, the
Re: (Score:1)
Yes, there is a Google's paper about MapReduce algorithm which might be used for the situation.
People whom I asked usually forgot that even to display 10 top links you cannot perform two queries with LIMIT 10 (or 20), one to select pages with most occurences for the word1, and then grep them to exclude those with word2: in this case you can get into multiple queries.
Re: (Score:1)
Heh, that reminds me of an interesting challenge I faced once.
I was creating a basic desktop query tool which would be used to summarize how much money had been spent in, say, a particular area on a particular kind of product. Products were categorized at various levels. For example a specific glass beaker would be classified as the exact item, as a glass beaker, as a laboratory supply made out of glass, and under laboratory supplies.
I had two interesting requirements. The first is that the database ship