> On 16 Mar 2016, at 16:37, Tom Lane <t...@sss.pgh.pa.us> wrote:
> 
> Andreas Joseph Krogh <andr...@visena.com> writes:
>> 1. Why isnt' folder_id part of the index-cond?
> 
> Because a GIN index is useless for sorting.

I don't see how gin inability to return sorted data relates to index condition.
In fact i tried to reproduce the example,
and if i change folder_id to int from bigint, then index condition with 
folder_id is used

         Index Cond: ((fts_all @@ '''hi'''::tsquery) AND (folder_id = 1))


> 
>> 2. Is there a way to make it use the (same) index to sort by 
>> received_timestamp?
> 
> No.
> 
>> 3. Using a GIN-index, is there a way to use the index at all for sorting?
> 
> No.
> 
>> 4. It doesn't seem like ts_rank uses the index for sorting either.
> 
> Same reason.
> 
>                       regards, tom lane
> 
> 
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