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From version 2.10 it is possible to adjust the number of fields that are to be returned from a resource. Its It's possible to both increase and decrease the number of fields from the default view. So if only field A and B from a resource is needed and the other X number of fields can be ignored, it can be specified in the header of the request. This will reduce the overhead of data transferred and improve performance. If more fields are needed in one request, to avoid making a second request to get all the data that is needed, this can also be done. So if fields A, B and C are returned in the default view, but also field D is needed, this can be specified in the header.
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Retrieving data from a resource may provide more information than needed. Fields with data to be returned can be specified by first adding a header field and then specifying the fields to be returned in the header field value. The header field value is specified as as a json message following same structure as the resource structure that is used when making the request. This enables fields to b e be specified in main- and sub-objects.
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