# query logic

1. get all nodes in the bbox
2. for each node:
 a. get all referring ways
 b. for each way
  1. recursively get all relation referers (no head-versions expansion)
  2. get all head versions of this way
  3. for each head way
   a. get all nodes
   b. for each node
    1. get all head versions of this node
    2. for each head node
     a. recursively get all relation referers (no head-versions expansion)
 c. recursively get all relation referers (no head-versions expansion)