SQL Parent-Child in same Table in Oracle - sql

Question

I need held understanding how to work with the following example.
Let's say I have these two tables:
**Table Name: Children**
Child Shirt_Color_ID Parent
Bob 1 Kate
Kate 2 Jack
Jack 3 Jill
. . .
. . .
**Table Name: Shirt_Colors**
Shirt_Color_ID Shirt_Color
1 Red
2 Blue
3 White
And I want to return a following table:
Child Child_Shirt_Color Parent Parent_Shirt_Color
Bob Red Kate Blue
How would I get the Parent_Shirt_Color in?
I got how to show Child, Child_Shirt_Color, Parent:
select
Children.Child,
Shirt_Colors.Shirt_Color,
Children.Parent
from
Children,
Shirt_Colors
where
Shirt_Colors.Shirt_Color_ID = Children.Shirt_Color_ID and
Children.Child = 'Bob';
Other examples I have looked at for this, talked about using "WITH," but get errors every time I try saying it is unsupported. Also, I have a very very long relation between parents and children, so I do not want the entire list returned - only 2-3 generations.
Using Oracle
Any help would be appreciated. Thanks!

Answer 1

You need CTE and used it for recursive queries.
http://technet.microsoft.com/en-us/library/ms186243(v=sql.105).aspx
Try following code:
DROP TABLE Children
DROP TABLE Shirt_Colors
CREATE TABLE Children(
Child varchar(20),
Shirt_Color_ID int,
Parent varchar(20)
)
CREATE TABLE Shirt_Colors
(
Shirt_Color_ID int,
Shirt_Color varchar(20)
)
INSERT INTO Shirt_Colors (Shirt_Color_ID, Shirt_Color)
VALUES (1, 'Red'),
(2, 'Blue'),
(3, 'White'),
(4, 'Yellow')
INSERT INTO Children (Child, Shirt_Color_ID, Parent)
VALUES ('Bob', 1, 'Kate'),
('Kate', 2, 'Jack'),
('Jack', 3, 'Jill'),
('Jill', 4, NULL)
select * from Children
;
WITH CTE (Child, Shirt_Color, Parent)
AS
(
SELECT
C.Child,
SC.Shirt_Color,
C.Parent
FROM Children C
INNER JOIN Shirt_Colors SC
ON C.Shirt_Color_ID = SC.Shirt_Color_ID
WHERE C.Parent IS NULL
UNION ALL
SELECT
C.Child,
SC.Shirt_Color,
C.Parent
FROM CTE
INNER JOIN Children C
ON CTE.Child = C.Parent
INNER JOIN Shirt_Colors SC
ON C.Shirt_Color_ID = SC.Shirt_Color_ID
)
SELECT
Child,
Shirt_Color,
Parent
FROM CTE