: I rewrite the prefix wildcard query consult* to (consult consult?*), it : works with highlighting. Do you think it's a possible solution? : Could you explain a little bit why put a "?" before "*" won't crash solr : if matching a lot of terms?
actually what i said was that Solr has an optimization to help reduce the likelyhood of crashing with prefix queries -- that optimization (using a PrefixFilter) doesn't work with highlighting. if you put a "?" in front of the "*" you force Solr to use a wildcard query, bypass the optimization, and get working highlighting -- but now you risk the same potential crashing behavior. the possibility of a "crash" stemms from the way Wildcard (and low level prefix) queries work -- they inspect the index to get a list of all the words that match the pattern, and then query on each of them ... this can be slow, but worse it can take up a lot of RAM, more ram then you may have ... so Lucene has a built in limit that controls how big it will let these queries get, it's configurable in solr using the "maxBooleanClauses" option in your solrconfig.xml. If you try to make a WildcardQuery with a pattern that matches more then that many terms in your index, the query will fail (but it's still possible Solr will crash if you configure this value to be so big that it the expanded query exhausts all of your ram) -Hoss
