Re: Indexam interface proposal - Mailing list pgsql-hackers

From Heikki Linnakangas
Subject Re: Indexam interface proposal
Date
Msg-id 45FE9680.8040107@enterprisedb.com
Whole thread Raw
In response to Re: Indexam interface proposal  (Teodor Sigaev <teodor@sigaev.ru>)
Responses Re: Indexam interface proposal  (Teodor Sigaev <teodor@sigaev.ru>)
List pgsql-hackers
Teodor Sigaev wrote:
>> Right, except that flag is per operator in operator class, and what 
>> I'm proposing is that the index could pass a flag per tuple in the scan. 
> 
> That might make sense even for GiST. Sometimes complex compressions is 
> used in GiST opclasses. If indexing value is rather small then it's 
> stored in index as is, but large value is compressed with lossy 
> techniques. So, GiST might return a tuple which is allowed to not recheck.

Interesting. So we'd add a flag to the index tuples in GiST indicating 
if the tuple is lossily compressed or not. The compress-function would 
set that flag when it performs lossy compression, and gistgettuple would 
return it to the caller.

That would completely replace the current RECHECK-option we have, right?

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com


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