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Question

super projections

  • January 25, 2019
  • 1 reply
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sreeblr
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Is it good to have more than one super projection per table with the two or more super projections differing in columns in the order by clause . I checked and found both projections for table are used

1 reply

Jim_Knicely
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  • February 1, 2019

I don't think it's a question of if it's good or bad to have more than one super projection per table, but a question of if more than one super projection is needed. If you have 2 super projections with different sort orders, they could service 2 different query workloads. But do you really need all of the columns in that second super projection? Maybe, but probably not. From a data load perceptive you want to limit the number of super projections. Does that make sense? Most clients tune a single super projection to service a majority of the queries, and then define 1 or 2 additional query specific projections that contain a small sub set of the table's columns.