Is it possible with Peewee to execute the following recursive CTE query?
The code creates a self-referencing table representing a tree structure, and the query finds all the parents of one element. (I am a SQL beginner, any advice for improvement is welcome).
CREATE TABLE Parts (
Id INTEGER PRIMARY KEY,
Desc TEXT,
ParentId INTEGER
);
INSERT INTO Parts VALUES (1, 'CEO', NULL);
INSERT INTO Parts VALUES (2, 'VIP Sales', 1);
INSERT INTO Parts VALUES (3, 'VIP Operations', 1);
INSERT INTO Parts VALUES (4, 'Sales Manager Europe', 2);
INSERT INTO Parts VALUES (5, 'Sales Manager USA', 2);
INSERT INTO Parts VALUES (6, 'Sales Rep Europe 1', 4);
INSERT INTO Parts VALUES (7, 'Sales Rep Europe 2', 4);
INSERT INTO Parts VALUES (8, 'Sales Rep USA 1', 5);
INSERT INTO Parts VALUES (9, 'Sales Rep USA 2', 5);
WITH RECURSIVE Cte (
Level,
Id,
Desc,
ParentId,
ParentDesc
) AS (
SELECT 0,
Child.Id,
Child.Desc,
Parent.Id,
Parent.Desc
FROM Parts AS Child
JOIN Parts AS Parent ON Child.ParentId = Parent.Id
WHERE Child.Desc = 'Sales Rep USA 1'
UNION ALL
SELECT Cte.Level + 1,
Child.Id,
Child.Desc,
Parent.Id,
Parent.Desc
FROM Parts as Child, Cte
JOIN Parts AS Parent ON Child.ParentId = Parent.Id
WHERE Child.Id = Cte.ParentId
)
SELECT * FROM Cte;
Peewee doesn't have any built-in facilities for constructing recursive queries. While it would be possible to hack it together using some of the SQL building-block classes, you're honestly probably better off just passing the whole SQL query into peewee's raw()
method:
http://docs.peewee-orm.com/en/latest/peewee/api.html#Model.raw