@Override
	public int getSize() {
		validate(lock);
		Table table = propertyTable;
		return table != null ? table.getRecordCount() : 0;
	}
Delete this property map and all underlying tables.
This method should be overidden if any table other than the 
default propertyTable is used.
@throws IOException if IO error occurs
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/database/properties/PropertyMapDB.java