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Solr proximity ordered vs unordered

In Solr you can perform an ordered proximity search using syntax 

"word1 word2"~10

By ordered, I mean word1 will always come before word2 in the document. I would like to know if there is an easy way to perform an unordered proximity search, ie. word1 and word2 occur within 10 words of each other and it doesn't matter which comes first.

One way to do this would be:

"word1 word2"~10 OR "word2 word1"~10

The above will work but I'm looking for something simpler, if possible.

Solution

  • Slop means how many word transpositions can occur. So "a b" is going to be different than "b a" because a different number of transpositions are allowed.

    • a foo b has positions (a,1), (foo, 2), (b, 3). To match (a,1), (b,2) will require one change: (b,2) => (b,3)
    • However, to match (b,1), (a,2) you will need (a,2) => (a,1) and (b,1) => (b,3), for a total of three position movements

    In general, if "a b"~n matches something, then "b a"~(n+2) will match it too.

    EDIT: I guess I never gave an answer. I see two options:

    1. If you want a slop of n, increase it to n+2
    2. Manually disjunctivize your search like you suggested

    I think #2 is probably better, unless your slop is very large to begin with.