 		}
 	}
 
+	public var core: Dictionary<String, CNValue>	{ get { return mDictionary		}}
 	public var rowCount: Int			{ get { return mDictionary.count	}}
 	public var columnCount: Int			{ get { return mFieldNames.count	}}
-	public var fieldNames: Array<String>		{ get { return mFieldNames		}}
-	public var core: Dictionary<String, CNValue>	{ get { return mDictionary		}}
+	public var allFieldNames: Array<String>		{ get { return mFieldNames		}}
+	public var activeFieldNames: Array<String> {
+		get { return mFieldNames }
+		set(names) { CNLog(logLevel: .error, message: "Can not overwrite field names", atFunction: #function, inFile: #file) }
+	}
 
 	public func fieldName(atIndex idx: Int) -> String? {
 		if 0<=idx && idx<mFieldNames.count {

{
	var rowCount: 		Int		{ get }
	var columnCount:	Int		{ get }
	var fieldNames:		Array<String> 	{ get }

	func fieldName(atIndex idx: Int) -> String?


		}

		/* Update column titles */
		let fnames = mTableInterface.activeFieldNames
		for i in 0..<mTableInterface.columnCount {
			let col = mTableView.tableColumns[i]
			col.identifier	= NSUserInterfaceItemIdentifier(fnames[i])
