Re: Optimize query for listing un-read messages

>
>
> Per-User caching does seem to be something that is going to be needed...
>
> Depending on how many users are being tracked would storing the "reader_id"
> in an indexed array improve matters? " SELECT ... FROM message WHERE NOT
> (1
> = ANY(reader_ids)) ; UPDATE message SET reader_ids = reader_ids || 1 WHERE
> messageid = ..." I'm not that familiar with how well indexes over arrays
> work or which kind is needed (i.e. gin/gist).
>
>
>
> "is_read" is one of many properties being tracked for a message...
>
>
​But you don't have to have all of them on the same table. Once you've
identified the messages in question performing a standard join onto a
supplemental detail table should be fairly straight-forward.

Do these other properties have values when "is_read" is false or only when
"is_read" is true? Since you already allow for the possibility of a
missing record (giving it the meaning of "not read")​ these other
properties cannot currently exist in that situation.

David J.

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