Re: selects from large tables

Nikk Anderson wrote:
> Hi,
>
> I tried a test cluster on a copy of our real data - all 10 million rows or
> so.  WOW!   The normal select performance improved drastically.
> Selecting 3 months worth of data was taking 146 seconds to retrieve.  After
> clustering it took 7.7 seconds!  We are now looking into ways we can
> automate clustering to keep the table up to date.  The cluster itself took
> around 2.5 hours.
>
> As our backend systems are writing hundreds of rows of data in per minute
> into the table that needs clustering - will cluster handle locking the
> tables when dropping the old, and renaming the clustered data?  What happens
> to the data being added to the table while cluster is running? Our backend
> systems may have some problems if the table does not exist when it tries to
> insert, and we don't want to lose any data.

CLUSTER will exclusively lock the table from read/write during the
CLUSTER.  Sorry.

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