I'm preparing an 'ideal' events fact table to hand off to our engineers to build. My question is, if we have an event timestamp field event_time
and I want to index the dates only, is it possible to index event_time::date
or must I request a separate date field based on the event_time for indexing purposes?
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Doug Fir
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3You can do `create index on ideal ((event_time::date));`. Whether it will be a benefit is something you would have to test. My suspicion is not, as querying on the `timestamp` means querying on the `date` anyway. – Adrian Klaver Dec 12 '21 at 17:36
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1You can create a secondary [auto generated] column for it or you can index the expression as shown by @AdrianKlavier. However, if you index the expression, make sure your queries use the exact same expression in the search predicates. Slight variations could prevent the index to be used. – The Impaler Dec 12 '21 at 18:19
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Got it, thanks for the info – Doug Fir Dec 12 '21 at 18:36
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Why have you got a timestamp in your fact table - how are you linking it to a dimension table? – NickW Dec 12 '21 at 20:25