Question: if we run the same select query twice on a historical database, will q recognize that it is a duplicate and avoid going back to the disk?
I mean:
q)a: select from HDB where date within (“d”$.z.z; -1+“d”$.z.z)
q)b: select from HDB where date within (“d”$.z.z; -1+“d”$.z.z)
Will q recognize that since data for b is already in memory it needn’t go back to the disk?
Thanks!
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no, but it will be in all kind of caches including the disks’,
hence it will be much faster the next time around
On 29 Jan 2011, at 11:24, K4 Monk wrote:
> Question: if we run the same select query twice on a historical =
database, will q recognize that it is a duplicate and avoid going back =
to the disk?
>
> I mean:
>
> q)a: select from HDB where date within (“d”$.z.z; -1+“d”$.z.z)
> q)b: select from HDB where date within (“d”$.z.z; -1+“d”$.z.z)
>
> Will q recognize that since data for b is already in memory it needn’t =
go back to the disk?
>
> Thanks!
>
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If you want in-memory caching handled by q, use views