Oracle tree query start with connect

Oracle tree query start with connect

I. Introduction
In Oracle, start with connect by (prior) is used to query data in a tree structure. Here, start with conditon gives the range of data searches, and connect by gives the conditions for Recursive queries. The prior keyword indicates the parent data, and the prior condition indicates the conditions for the child data to meet the parent data. As follows:
Start with id = '000000' connect by prior parent_id = id and prior num = 5
Indicates that the query id is 10001, And the recursive query parent_id = id is 5 Records.
Ii. Instances
1. Construct Data

1 -- table structure 2