FileMaker Anchor / Buoy Relationships Do Create Redundant TOs

From Dwayne Wright PMP, PMI-ACP
Certified FileMaker Developer

TWITTER: dwaynewright
YOUTUBE: FileMakerThoughts

The bi-directional feature in FileMaker relationships is a powerful feature and allows you to write tighter code in regards to your relationships. However, it is a feature I have decided to totally do without and so does the true Anchor / Buoy design concept.

Say that you have a relationship between Invoices and Clients so that you can see client information from an invoice record. So you have that relationship setup and now you want to have a portal of related invoices that can be seen from a client record.

In traditional relationship design, you can use the same relationship setting between invoices to clients. In Anchor/Buoy, you have to have two relationships because no two main tables can use the same relationship.

So you can say that Anchor / Buoy is a setup of one way streets and two way streets are not allowed. In light of this one example, Anchor / Buoy design makes almost zero sense. However, if you are talking about a solution with 20 or more highly relationship connected tables, you are going to have so many bidirectional relationships that it is going to be hard to keep them straight.

If you use a relationship design approach other than Anchor / Buoy, you will likely see all possible table occurrences in TO related pick lists because almost everything links to everything. If you use an Anchor/Buoy relationship design approach, this list is filtered because no two base tables touch (again because table occurrences are organized into groups or islands). So you can quickly and effectively choose just the related table occurrences you need and not choose a problematic table occurrence.

So you will have a large number of redundant TOs but if you manage them correctly, they are beneficial from a design and a project management perspective.

Here are some links to other posts that might be of interest in regards to this topic...
Anchor/Buoy, A Closer Look At Its Advantages
So, What Are The Benefits Of Anchor / Buoy
More About Layout Context And Table Occurrences
More About Calculation Context And Table Occurrences
Benefits Anchor / Buoy (the quick list)
Anchor / Buoy Segmentation Makes Better Printing
More info about the author and FileMaker in general, contact me at

© 2008 - Dwayne Wright -

The material on this document is offered AS IS. There is NO REPRESENTATION OR WARRANTY, expressed or implied, nor does any other contributor to this document. WARRANTIES OF MERCHANT ABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY DISCLAIMED. Consequential and incidental damages are expressly excluded. FileMaker Pro is the registered trademark of FileMaker Inc.