My initial request was about a way to build up a tsquery that was made similar to what plainto_tsquery does but using | inspite of & as a glue. But at the end of the day I'd like to find similar tsvectors and rank them. I've a table containing several fields that contribute to build up a weighted tsvector. I'd like to pick up a tsvector and find which are the N most similar ones. I've found this: http://domas.monkus.lt/document-similarity-postgresql That's not really too far from what I was trying to do. But I have precomputed tsvectors (I think turning text into a tsvector should be a more expensive operation than string replacement) and I'd like to conserve weights. I'm not really sure but I think a lexeme can actually contain a ' or a space (depending on stemmer/parser?), so I'd have to take care of escaping etc... Since there is no direct access to the elements of a tsvector... the only "correct" way I see to build the query would be to manually rebuild the tsvector and getting back the result as a record using ts_debug and ts_lexize... that looks a bit a PITA. I don't even think that having direct access to elements of a tsvector will completely solve the problem since tsvectors store positions too, but it will be a step forward in making easier to compare documents to find similar ones. An operator that check the intersection of tsvectors would come handy. Adding a ts_rank(tsvector, tsvector) will surely help too. thanks -- Ivan Sergio Borgonovo http://www.webthatworks.it -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
