Hi Milan, thx for your report.
I try to see a check, and effectively I notice the problem is in the qgrams_distance when used the metrics option. As reported in the readme, the stringmetrics extension is based on the https://github.com/jokillsya/libsimmetrics library. The code on the metrics is integrally take from the sample of that library. I guess the problem you report is due to a static allocation (or similar effect) that is not appropriated when in the same query the same function is called more than one time. Actually I dont know if the problem is in the sqlite side of my code or in the original code of the symmetrics library. I try to resolve this firstly question when and if I find a few of time. However patches are welcomes. :) Regards, Andrea Peri. Il 06/03/2015 17:00, Milan Roubal ha scritto: > Dear all, > I have some problems with > https://github.com/aperi2007/libstringmetrics . For example: > When I use "similarity" in qgrams_distance, I get good results. But > when I use "metric", it works only if it is only once in the query. > When there are 2 different usages, they somehow interfere together. Is > this the right place where to report such problem? > >> sqlite3 > SQLite version 3.8.8.3 2015-02-25 13:29:11 > Enter ".help" for usage hints. > Connected to a transient in-memory database. > Use ".open FILENAME" to reopen on a persistent database. > > sqlite> select load_extension("libstringmetrics.dll"); > > sqlite> select a.firstname, b.firstname, a.lastname, b.lastname, > ...> stringmetrics("qgrams_distance","similarity",a.firstname, > b.firstname,"") first_dist, > ...> stringmetrics("qgrams_distance","similarity",a.lastname, > b.lastname,"") last_dist > ...> from > ...> (select "Milan" as firstname, "Roubal" as lastname ) a, > ...> (select "Milan" as firstname, "roubal" as lastname ) b > ...> ; > Milan|Milan|Roubal|roubal|100.0|62.5 > > sqlite> select a.firstname, b.firstname, a.lastname, b.lastname, > ...> stringmetrics("qgrams_distance","metric",a.firstname, > b.firstname,"") first_dist, > ...> stringmetrics("qgrams_distance","metric",a.lastname, > b.lastname,"") last_dist > ...> from > ...> (select "Milan" as firstname, "Roubal" as lastname ) a, > ...> (select "Milan" as firstname, "roubal" as lastname ) b > ...> ; > Milan|Milan|Roubal|roubal|6|6 > > sqlite> select a.firstname, b.firstname, a.lastname, b.lastname, > ...> stringmetrics("qgrams_distance","metric",a.firstname, > b.firstname,"") first_dist > ...> from > ...> (select "Milan" as firstname, "Roubal" as lastname ) a, > ...> (select "Milan" as firstname, "roubal" as lastname ) b > ...> ; > Milan|Milan|Roubal|roubal|0 > > Thank you > Best Regards > Milan > _______________________________________________ > sqlite-users mailing list > sqlite-users at mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
