It is recommended that you spend the time to go through your attribute set manually, to ensure you keep what you need and discard what you don’t.
Make a Backup
Make a backup copy of your project. If you later inadvertently delete attributes, you can use Attribute Manager and append them again from the backup copy.
Remove Unnecessary Attributes
- Use the tab pages of the Attribute Manager to view the lists of each attribute type and delete the ones you do not use and will not need. Go through each attribute type (each tab page) one by one.
- For each attribute type, delete each unneeded attribute one by one (select it in Attribute Manager, then click Delete).
- If you are not sure about a particular attribute, you can rename it (e.g. append the tag _delete to its name), then review the project to see if it is in fact being used.
- Do not use the Purge Unused command unless you are confident that your project is not using any of the attributes to be purged.
o If any of your element defaults or Favorites uses a particular attribute, but has not been placed in the project, the Purge command will delete that attribute as “unused.”
o The Purge command will delete attributes that are used in GDL scripts of Library Parts.
Review Element Defaults and Favorites
When you migrate a project to ArchiCAD 17, Default and Favorite element settings will potentially generate new attributes when migrating. Before migrating, make sure your defaults/favorites are necessary and up to date, based on elements that are actually used in the Project. (ArchiCAD 17 will generate new attributes to correspond to defaults or favorites, even if they are not actually used in placed elements).