Recursive Node Hierarchy Extraction In SPL Vs SQL
SQL solution for multi-level self-association structure: use recursive CTEs to find hierarchy and zones. SPL provides direct functions for recursive references.
A certain table in the MS SQL database has a multi-level self-association structure, where the second field parent node ID is a foreign key pointing to the first field node ID of the table, and the
third field is a zone.
Now we need to find the hierarchy of nodes with a higher level of 2 or more, as well as the zones of the highest-level nodes. For example, the first record has 3 levels of hierarchy, which are 5-11-15, and the highest level is 15; The second record has two levels of superiors, namely 6-12, with the highest level being 12.
SQL solution：
WITH dt AS (
SELECT
temp.produ...