Specifications of the specialized version of the DD-API for ecology

View project on GitHub


Pagination is important for results sets that have potentially a large amount of items in them. Therefor, implementation of a paging algorithm is required. But even paging algorithms can differ per implementation, yielding unexpected results. To avoid confusion and undesired results, the DD-ECO-API defines the behavior of the paging algorithm.

Three items determine the query results:

  • page parameter (starts with 1)
  • pagesize parameter (minimum is 1, defaults and max are determined by the provider)
  • filter parameter (defaults to empty). If defines the query filter.

The paging logic is as follows:

  1. Apply the filter to the data.
  2. Skip (pagesize * (page - 1) rows.
  3. Return (pagesize) records.

For queries specified with parameter nocount specified:

  1. Apply the filter to the data.
  2. Skip (pagesize * (page - 1)) rows.
  3. Retrieve (pagesize + 1) rows. If only (pagesize) or less rows are returned, there is no next page.
  4. Return (pagesize) rows

A consumer should be able to safely assume the following:

  • If the number of results returned is less than pagesize, there will be no more pages to be retrieved, so the end of the result set is reached.