Pivotal Entry-based Method o Too many tuples e Want to group the children together [1,6 [15] [6,6] 22 [1,1]e[2,2] u[3, 5 (1【34] r55 8 a B33]t44a 10 19 26 D:4 D:5 D:6 2/2/2021 Topk Search(@ ICD E2013Pivotal Entry-based Method 2/2/2021 TopkSearch @ ICDE2013 39/42  Too many tuples  Want to group the children together