David Hoksza <david(dot)hoksza(at)seznam(dot)cz> writes:
> Hi, could anybody tell me which variation of B-tree PostgreSQL uses, that
> it can handle more than one column?
Plain old b+ tree ... we just treat the keys as compound, ie the
"compare" operation compares columns until finding a difference.
> Some link would be great.
Use the source Luke ...
http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/nbtree/
regards, tom lane