Hello all,
I’m developing a specialist application that needs a different kind of referential integrity! I need interval referential integrity where the bounds of the referenced interval must overlaps (or be equal) the bounds of the referencing interval!
For example,
-------------------------------------------------------------------------------------------------------------------------------------------
-- I did the functions IN and OUT to get this working
Create type t_interval (
Lower int,
Upper int
);
CREATE TABLE tableA (
tableA_id integer,
name varchar(30),
boundA t_interval,
constraint pk_tableA primary key (tableA, boundA)
);
CREATE TABLE tableB (
tableB_id integer,
boundB t_interval,
constraint fk_B_A foreign key (tableB_id, boundB) references tableA
);
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So, tableA.boundA OVERLAPS tableB.boundB!
Example,
Insert into tableA values (1, ‘test 1’, ‘(1, 5)’);
Insert into tableB values (1, ‘(2, 4)’); à POSSIBLE
Insert into tableB values (1, ‘(1, 3)’); à POSSIBLE
Insert into tableB values (1, ‘(3, 7)’); à NOT POSSIBLE
I know that I need to change some (may be a lot of) things in the source code. Specifically in the RI_TRIGGER.C (isn´t???). But I need some help to do this!
Anyone have an idea?
Thanks in advance!