Once you have queried features from a spatial database, removing a feature (instance) can have two different meanings.
• Removing it from the display, for example when you’ve accidentally queried too many features.• Removing it from the database, because the spatial object should be deleted permanently.
Erase Cached Instances: This tool removes feature instances from the local DGN cache and can be limited by a selection set or spatial filter. The features are not deleted from the database.
Delete Element: The standard MicroStation Delete Element tool performs a delete operation, meaning that the features will be removed from the database during a post operation. Note that features need to be locked before you can delete them.
Remove queried features using Erase Cached Instances:
1) Select features to be erased with the Element Selection tool or by placing a fence around them. 2) Select Erase Cached Instances from the Spatial Tools toolbar and follow the prompts.
Deleting features from the database
1) Add the queried features to delete into a selection set or fence. 2) Select Lock from the Spatial Tools toolbar and accept with a datapoint.3) Select Delete Element and accept with a datapoint.4) Post the changes to the spatial database by choosing Post Changes from the Spatial Tools toolbar and enter a data point.