Re: slow query performance

Dave Weaver wrote:

>>- clustering the "obs" table on "station"
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>Sorry, I don't understand what you mean by this - can you explain?
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Supposing obs_pkey is on (station, valid_time):

cluster obs_pkey on obs

will re-order the rows in obs based on the index obs_pkey. (This is
clustering on 'station' and 'valid_time', to do just station you could
use an index on just 'station').

The down side is that the row ordering is slowly lost as rows are
updated, so periodic running of the cluster command is needed - this is
a pain as it will take a while for 13 million row table.

regards

Mark