Re: GiST index on data types that require compression - Mailing list pgsql-hackers

From Teodor Sigaev
Subject Re: GiST index on data types that require compression
Date
Msg-id 3B0E8861.5040508@stack.net
Whole thread Raw
In response to Re: GiST index on data types that require compression  (Oleg Bartunov <oleg@sai.msu.su>)
List pgsql-hackers
 > So, may by add to pg_opclass two fields?> bool is_varlena_key> bool is_lossy_compress


Sorry, I was wrong. In GiST, index_formtuple doesn't know about size of 
fixed-length type of keys, because only loadable module has information 
about structure of key. So, may be it needs to have function which 
return size of key or index_formtuple must looks at GISTENTRY.bytes( 
Note: A lot of currrent implementation of GiST modules don't set value 
GISTENTRY.bytes ). Or fields in pg_opclass:
int len_key
bool is_lossy_compress

if len_key==-1 then key is varlena type.

-- 
Teodor Sigaev
teodor@stack.net




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