Is this possible with the current websearch_to_tsquery function? Thanks.
Hello everyone, I am wondering if > AROUND(N) or <N, M> is still possible? I found this thread below and the > original post > https://www.postgresql.org/message-id/fe931111ff7e9ad79196486ada79e268%40postgrespro.ru > mentioned the proposed feature: 'New operator AROUND(N). It matches if the > distance between words(or maybe phrases) is less than or equal to N.' > > currently in tsquery_phrase(query1 tsquery, query2 tsquery, distance > integer) the distaince is searching a fixed distance, is there way to > search maximum distance so the search returns query1 followed by query2 up > to a certain distance? like the AROUND(N) or <N, M> mentioned in the > thread? > > Thank you! > > > > On Mon, Jul 22, 2019 at 9:13 AM Dmitry Ivanov <d.iva...@postgrespro.ru> > wrote: > >> Hi everyone, >> >> I'd like to share some intermediate results. Here's what has changed: >> >> >> 1. OR operator is now case-insensitive. Moreover, trailing whitespace is >> no longer used to identify it: >> >> select websearch_to_tsquery('simple', 'abc or'); >> websearch_to_tsquery >> ---------------------- >> 'abc' & 'or' >> (1 row) >> >> select websearch_to_tsquery('simple', 'abc or(def)'); >> websearch_to_tsquery >> ---------------------- >> 'abc' | 'def' >> (1 row) >> >> select websearch_to_tsquery('simple', 'abc or!def'); >> websearch_to_tsquery >> ---------------------- >> 'abc' | 'def' >> (1 row) >> >> >> 2. AROUND(N) has been dropped. I hope that <N, M> operator will allow us >> to implement it with a few lines of code. >> >> 3. websearch_to_tsquery() now tolerates various syntax errors, for >> instance: >> >> Misused operators: >> >> 'abc &' >> '| abc' >> '<- def' >> >> Missing parentheses: >> >> 'abc & (def <-> (cat or rat' >> >> Other sorts of nonsense: >> >> 'abc &--|| def' => 'abc' & !!'def' >> 'abc:def' => 'abc':D & 'ef' >> >> This, however, doesn't mean that the result will always be adequate (who >> would have thought?). Overall, current implementation follows the GIGO >> principle. In theory, this would allow us to use user-supplied websearch >> strings (but see gotchas), even if they don't make much sense. Better >> then nothing, right? >> >> 4. A small refactoring: I've replaced all WAIT* macros with a enum for >> better debugging (names look much nicer in GDB). Hope this is >> acceptable. >> >> 5. Finally, I've added a few more comments and tests. I haven't checked >> the code coverage, though. >> >> >> A few gotchas: >> >> I haven't touched gettoken_tsvector() yet. As a result, the following >> queries produce errors: >> >> select websearch_to_tsquery('simple', ''''); >> ERROR: syntax error in tsquery: "'" >> >> select websearch_to_tsquery('simple', '\'); >> ERROR: there is no escaped character: "\" >> >> Maybe there's more. The question is: should we fix those, or it's fine >> as it is? I don't have a strong opinion about this. >> >> -- >> Dmitry Ivanov >> Postgres Professional: http://www.postgrespro.com >> The Russian Postgres Company > >
