There are two ways to change a Digital Object's parent. One is through the Hyacinth GUI and the other is through a CSV update.
Updating Parents Using the GUI
When viewing a Hyacinth object in the GUI, there's a "Parents" link in the secondary navbar.
After clicking on this link, you'll get to a page where you can remove old parents (based on parent PID) by checking off the ones you want to remove and clicking the "Remove Selected Parents" button.
To add a new parent, simply find the pid of that parent and enter it into the "Add Parent Item" field and then click "Add". Your object will be appended to the end of that parent's current set of child Digital Objects.
Updating Parents via CSV
The GUI is usual faster and easier to work with for updating a single Digital Object's parent, but you can also use CSV import to update the parents for one of more objects. Export a CSV containing the Digital objects for which you want to update parents:
For this CSV, you can remove out all columns other than _pid and any columns that start with "_parent_digital_objects-". They're not necessary because we're only planning on updating parent-child relationships here, so it's simpler to work with a smaller set of columns. For the _parent_digital_objects-* columns for a given row, remove any parent pids that should be disconnected from this child and add any new parents that this child should have:
And then do a regular CSV import. The old parents will be disconnected and this Digital Object will be appended to the end of the child list for the newly-added parents.
Important note: If this Digital Object has more than one parent, make sure not to omit the pid columns for its other parent objects that you still want it to be associated with. This is why it's better to do a CSV export of existing Hyacinth objects rather than creating a new CSV from scratch, since if an object has two parents and you only include one "_parent_digital_objects-1.pid" column in the spreadsheet, that's telling Hyacinth to disconnect this object from any other current parents that were omitted.