%Library.CacheSQLStorage
From CacheWiki
This class implements the Cache SQL Storage Scheme for persistent classes.
StorageToLogical
This method is not implemented consistently for this class. When code is generated for a class that has this storage scheme the StorageToLogical and LogicalToStorage methods are not implemented for IDKEY properties. This means that subscripts do not get converted from their on-disk format to their in-memory format.
This is a known bug in all versions of Cache.