2013/5/31 Amit Langote <amitlangot...@gmail.com> > > On Thu, May 30, 2013 at 11:47 PM, Robert Haas <robertmh...@gmail.com> wrote: > > On Wed, May 29, 2013 at 10:51 PM, Amit Langote <amitlangot...@gmail.com> > > wrote: > >> So, it appears, for search strings consisting of 2 (or < 3) > >> characters, trigrams can not be utilized. No? > > > > I think that's right. "trigram" means a sequence of three characters, > > and what's stored in the indexes are three-character sequences from > > the original text. > > > > Was there any improvement to pg_trgm in recent past that could make it > better for partial matching (the case in question I suppose) or is > partial-matching a different thing altogether? >
Hi Amit, following emails are discussed about partial match of pg_trgm. I hope will this help. <http://www.postgresql.org/message-id/cahgqgwfjshvv2ngme19wdtw9tefw_w7h2ns4e+yysjkb9wd...@mail.gmail.com> as you may know, if search string contains multibyte characters trigram key is converted to CRC of 4 byte and it is used as key. (but only use upper 3 byte from CRC) so we can do partial matching if KEEPONLYALNUM is enabled. Regards, -------- Masahiko Sawada -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
