Re: fate of CLUSTER command ?

Christopher Kings-Lynne wrote:
> > Clustering on one index doesn't decrease the performance of the other
> > indexes.  Also, only >=7.3 will preserve all indexes during cluster.
> 
> Sure it must?  Since you are rearranging all on-disk rows to match a
> particular index (say user_id, username) then it will slow down other
> indexes (eg one just on username).

It will slow down other index scans only if there was some clustering on
those indexes before you ran the CLUSTER command.

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