issues with spellcheck.maxCollationTries and spellcheck.collateExtendedResults

[Markus Jelsma]

Hi,

We've had some issues with a bad zero-hits collation being returned for a two 
word query where one word was only one edit away from the required collation. 
With spellcheck.maxCollations to a reasonable number we saw the various 
suggestions without the required collation. We decreased 
thresholdTokenFrequency to make it appear in the list of collations. However, 
with collateExtendedResults=true the hits field for each collation was zero, 
which is incorrect.

Required collation=huub stapel (two hits) and q=huup stapel

      "collation":{
        "collationQuery":"heup stapel",
        "hits":0,
        "misspellingsAndCorrections":{
          "huup":"heup"}},
      "collation":{
        "collationQuery":"hugo stapel",
        "hits":0,
        "misspellingsAndCorrections":{
          "huup":"hugo"}},
      "collation":{
        "collationQuery":"hulp stapel",
        "hits":0,
        "misspellingsAndCorrections":{
          "huup":"hulp"}},
      "collation":{
        "collationQuery":"hup stapel",
        "hits":0,
        "misspellingsAndCorrections":{
          "huup":"hup"}},
      "collation":{
        "collationQuery":"huub stapel",
        "hits":0,
        "misspellingsAndCorrections":{
          "huup":"huub"}},
      "collation":{
        "collationQuery":"huur stapel",
        "hits":0,
        "misspellingsAndCorrections":{
          "huup":"huur"}}}}}

Now, with maxCollationTries set to 3 or higher we finally get the required 
collation and the only collation able to return results. How can we determine 
the best value for maxCollationTries regarding the decrease of the 
thresholdTokenFrequency? Why is hits always zero?

This is with a today's build and distributed search enabled.

Thanks,
Markus