Strategy for arbitrary predicate queries in Couchdb

Question

We have an application that can greatly benefit from using a document-based data warehouse, such as CouchDB. But we have a case of using a query that I am trying to implement using Map Reduce.

Our documents really contain only two types of data:

• Numeric attributes
• Logical attributes

Boolean attributes essentially mark a document as belonging to one or more non-exclusive sets. Numeric attributes always need only be summarized. One way to structure a document is as follows:

{
  "id": 3123123,
  "attr": {"x": 2, "y": 4, "z": 6},
  "sets": ["A", "B", "C"]
}

Using this structure, it is easy to calculate the aggregate values ​​of x, y, z for the sets A, B, and C, but it becomes more complicated if you want to see aggregates for intersections such as A & C.

ABC ( "A, B, C, AB, AC, BC, ABC" ), , . 80 , , .

, CouchDB, , , MongoDB - .

- ?

Answer 1

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, , (4 3), (8 4), - (16 5). (10- 500 -).

, ( ) , ( , ). - , , .

, 2 ⁿ / ( "" , ). . , " " ( , ), .