I have run into similar issues regarding this table and extracting information out of the constraints column. I attempted to run your code samples but they do not run. Do you happen to have a full code sample that you can supply?

Basically I just want to extract the ID's out of that constraints column for a specific row on the ConstraintBasedGroupBase table and put them into another table so I can select against them. Why in the world they store the resource Id's like this is beyond me!