Re: Is cycle references?

On Wed, 1 Nov 2000 limin(at)www(dot)pumpkinnet(dot)com wrote:

> The db schema we have need to do a cycle references. I.e.,
> an attribute in table_1 references the key in table_2 and
> an attribute in table_2 references the key in table_1. However,
> PostgreSQL does not allow us to make reference to an "non-existing" table!
>
> Is there any work-around on this issue?

I had the same problem. You can play around with creating the tables
without the RI checks and adding the constraints later, but I found this
clumsy.

The solution I used was to have a third table with attributes referencing
keys from table_1 and table_2. This avoids the problem of inserting
references to keys which don't exist yet, and you can use joins from
table_[12] to table_3 to do the same queries you would have done with the
cross-referential tables.
--
Tod McQuillin