field_purge_instance($instance) Delete the row for this instance from the field_config_instance table. It is assumed that all data for the instance has already been deleted. Read more about field_purge_instance($instance)
field_purge_batch($batch_size) Purge a batch of fields that are marked deleted. Read more about field_purge_batch($batch_size)
field_info_cache_clear() Clears the field info cache without clearing the field data cache. Read more about field_info_cache_clear()
