Hi,
I'm working on a GiST opclass to support prefix searching as presented here:
http://pgsql.tapoueh.org/site/html/prefix/index.htmlhttp://prefix.projects.postgresql.org/README.html
http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/prefix/prefix/
In order to have a much more efficient index, I received the advice to
implement a prefix range datatype then base the picksplit() and union()
implementation on top of it.
So... where do I start to create a varlena datatype which has to store the 3
following values: text prefix, char start, char end.
It's not clear for me whether this is what I need to provide:
typedef struct
{ int32 vl_len_; char start; char end; text prefix;
} prefix_range;
In particular, I've been taught a varlena definition can not contain pointers,
and I've no idea how to embed a text into another varlena...
Regards,
--
dim