An ADO.NET multi-database, multi-tier solution

using System;
using System.Data;

namespace MultiTier.Data {

	public abstract class DataTier {

		private DataTable dtDataTable;
		private Exception exException;
		private long lngAffectedRecords;
		private string strConnectionString;
		private string strTableName;

		private DataTier() {
		}

		protected DataTier(string connection) {
			this.ConnectionString = connection;
			this.ConstructDataAdapter();
		}

		protected DataTier(string connection, string tableName) {
            this.ConnectionString = connection;
			this.TableName = tableName;
			this.ConstructDataAdapter();
		}
		
		protected DataTable Table {
			get { return dtDataTable; }
			set { dtDataTable = value; }
		}

		public string ConnectionString {
			get { return strConnectionString; }
			set { strConnectionString = value; }
		}

		public string TableName {
			get { return strTableName; }
			set { strTableName = value; }
		}

		public long AffectedRecords {
			get { return lngAffectedRecords; }
			set { lngAffectedRecords = value; }
		}

		public Exception Exception {
			get { return exException; }
			set { exException = value; }
		}

		protected abstract void ConstructDataAdapter();

		public abstract DataTable ReadData();

		public abstract void SaveData(DataTable dataTable);

		public abstract void InitializeConnection();
	}
}