Say I have a table of items representing a tree-like structured data, and I would like to continuously tracing upward until I get to the top node, marked by a parent_id of NULL. What would my MS SQL CTE (common table expression) look like?
For example, if I were to get the path to get to the top from Bender, it would look like
Comedy
Futurama
Bender
Thanks, and here's the sample data:
DECLARE @t Table(id int, description varchar(50), parent_id int)
INSERT INTO @T
SELECT 1, 'Comedy', null UNION
SELECT 2, 'Futurama', 1 UNION
SELECT 3, 'Dr. Zoidberg', 2 UNION
SELECT 4, 'Bender', 2 UNION
SELECT 5, 'Stand-up', 1 UNION
SELECT 6, 'Unfunny', 5 UNION
SELECT 7, 'Dane Cook', 6
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