Got a client with an interesting problem I haven't seen before.
They have a table that's self-joined to form a hierarchy of parents and
children. When attempting to change the primary key of a parent, they
get a "Trigger Failed" error and AERROR returns "Illegal recursion in
rule evaluation."
Here's a way to repro:
CREATE DATABASE testri
CREATE TABLE testtable (iKeyPK I, iParentFK i)
INSERT INTO testtable VALUES (1,1)
INSERT INTO testtable VALUES (2,1)
INSERT INTO testtable VALUES (3,1)
INSERT INTO testtable VALUES (4,1)
INSERT INTO testtable VALUES (5,2)
INSERT INTO testtable VALUES (6,2)
* Modify the database and define indexes for both keys. iKeyPK should
be a primary index.
* Define a self-join relationship in the database by dragging the
primary index to the iParentFK index.
* Click on the relatiionship and define referential integrity as
Cascade-Restrict-Restrict
set multilocks on
browse
* Try to change the first record (1,1) to (6,1)
ideally, the client is looking for a solution we can keep in the
triggers, as data is updated both through an application and from
browses. Suggestions welcomed.
Ted Roche
Ted Roche & Associates, LLC
http://www.tedroche.com
©2004 Ted Roche |
