how to form a tree structure from DB2 Table(s)?
Please refer to this question database-structure-for-tre开发者_如何学运维e-data-structure
Is this possible in DB2 Database? I know it is possible in Oracle using START WITH and CONNECT BY, i don't have any idea in DB2, Is it possible to achieve this in DB2?
Thanks!
Is is possible with DB2, here is a link for reference.
Basically, you use the WITH syntax. Taken from the link, assume we have this table:
CREATE TABLE emp(empid INTEGER NOT NULL PRIMARY KEY,
name VARCHAR(10),
salary DECIMAL(9, 2),
mgrid INTEGER);
We can use this query:
WITH n(level, empid, name) AS
(SELECT 1, empid, name
FROM emp
WHERE name = 'Goyal'
UNION ALL
SELECT n.level + 1, nplus1.empid, nplus1.name
FROM emp as nplus1, n
WHERE n.empid = nplus1.mgrid)
SELECT level, name FROM n;
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