key value - How to get distict count on dynamodb on billion objects? -

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what efficent way query dynamodb objects ?

such objects have ten properties , want distinct count based on 3 properties .

in case need counters it's better use atomiccounters (http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/workingwithdditems.html). in case, dynamodb doesn't support out of box keys composed out of 3 attributes, unless concatenate them, option create redundant table key concatenation of 3 attributes , each manage objects, update atomiccounter (add, delete, update - not needed actually).

then query counter, avoiding scans. so, it's space complexity gain speed of retrieving data.


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