Re: pg_migrator and an 8.3-compatible tsvector data type

Bruce,

> The ordering of the lexems was changed:
>
>     /*
>      * Convert 8.3 tsvector to 8.4
>      *
>      * 8.3 sorts lexemes by its length and if lengths are the same then it uses
>      * alphabetic order;  8.4 sorts lexemes in lexicographical order, e.g.
>      *
>      * =>  SELECT 'c bb aaa'::tsvector;
>      *     tsvector
>      * ----------------
>      *  'aaa' 'bb' 'c'         -- 8.4
>      *  'c' 'bb' 'aaa'         -- 8.3
>      */

What does that get us in terms of performance etc.?

Given that it's going to prevent users of Tsearch from 
upgrading-in-place, the format change ought to be giving us some serious 
gains.  Otherwise we should put it off until we need to make other 
datatype changes.

-- 
Josh Berkus
PostgreSQL Experts Inc.
www.pgexperts.com