Algorithm 2: Skyline query based on the data node tree algorithm

Input: table SCH, table Visited, data node tree T, local queue L, query node set Q

Output: the spatial skyline data ST based on T

1: regard the root node of data node tree T as the father node

2: for each of the father node do

3: if the father node has the local queue L

4: then the pointer point to the first record of the father node local queue L, determine dominance relation of the data point p corresponding to the record with the data node in the local table SCH

5: if P is dominated by the node in table SCH

6: then regard p as the new father node, then conduct step 2

7: if p is not dominated by the node in table SCH and do not dominate any node in SCH

8: then insert p to ST, and regard p as new father node, then conduct step 2

9: if p is not dominated by the node in table SCH and dominate the node in table SCH

9: if p is not dominated by the node in table SCH and dominate the node in table SCH

10: then insert p to ST, delete the dominated node in SCH, and regard p as new father node, then conduct step 2

11: if the father node do not has the local queue L

12: then return to the local queue of the father node of p, move the pointer to the next one and regard it as the new father node, then conduct step 2

13: end for