Pivotal Entry-based Method Extending cells 0123456 s r a i t 0 P1:(2,1)(1,2)(2,2) 01234 sera 56 2/2/2021 Topk Search(@ ICD E2013Pivotal Entry-based Method 2/2/2021 TopkSearch @ ICDE2013 30/42 Extending Cells P0 : (1,1) P1 : (2,1) (1,2) (2,2)