Is it reasonable to rebuild time to time projections?

There is not need to rebuild projections, the data is loaded in the right format. if you see a degradation in performance when you load the data, it may be related to data fragmentation in too many ros and mergeout not catching up. So look at the storage_containers and see if there are too many ros containers and check the tuple_mover_activities to see if mergeouts are happening for the projection. You should have 1 ROS per inactive partition.

You can always force a mergeout by doing select do_tm_task('mergeout','<table>') but be aware that this could be resource intensive as it will treat every partition as inactive.

Hope this helps.

Eugenia

Hi Eugenia,

The data structure is certainly correct but can be reasonably reconstruct the projection to improve the performance of queries to the data? Thanks in advance.

Igor

Projectiosn are not rebuild. In that case you need to create a new projection. If you want to keep both projections is OK or you can drop the old projection a leave the new one.

Hope this helps.

Eugenia

Thanks Eugenia, your post is very helpful for me.