Yate database IDs, track and album, are unique identifers which can be stored as UDTIs in tracks. The IDs can be created by the Database ID action statement and by the Actions>Database ID menu item. If you're going to be using Yata databases it is strongly recommend that you use these constructs. The IDs ensure that database content can be updated even if a track is renamed or moved.
The IDs can be used with export sets to create Album and Track databases which have additional references to albums and tracks. When setting you can elect to only set the ID if it is missing or in the case of Yate Album IDs, inconsistant.
The Database ID functions ensure that every selected track with the same album field will be assigned the same id for Set Yate Album ID.
When used as an action statement, the function operates in all execution modes. Doing a Set Yate Album ID in grouped mode will never have the desired results. Note that when the functionality is invoked from the UI, the effective mode is never grouped.
If you are interested in the type of value generated see Preferences-Actions.