On 20 June 2012 15:10, Greg Stark <st...@mit.edu> wrote: > On Sun, Jun 17, 2012 at 9:26 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: >> The trick for hashing such datatypes is to be able to guarantee that >> "equal" values hash to the same hash code, which is typically possible >> as long as you know the equality rules well enough. We could possibly >> do that for text with pure-strcoll equality if we knew all the details >> of what strcoll would consider "equal", but we do not. > > It occurs to me that strxfrm would answer this question. If we made > the hash function hash the result of strxfrm then we could make > equality use strcoll and not fall back to strcmp.
What about per-column collations? -- Peter Geoghegan http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training and Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
