public static List executeQuery(String sql) {
		Statement stmt = null;
		Connection con = null;
		ResultSet rst = null;
		List resultList = new LinkedList();
		try {
			con = DBConnection.createConnection();
			stmt = con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
					ResultSet.CONCUR_READ_ONLY);
			rst = stmt.executeQuery(sql);
			int n = rst.getMetaData().getColumnCount();//取得总列数
			while ( rst.next() ) {
				Map map = new HashMap();
				for (int i = 1; i <= n; i++) {					
					map.put(rst.getMetaData().getCatalogName(i), rst.getObject(i));
				}
				resultList.add(map);
			}
		} catch (SQLException e) {
			e.printStackTrace();
			return null;
		} finally {
			DBConnection.releaseResultSet(rst);// 释放资源
			DBConnection.releaseStatement(stmt);
			DBConnection.releaseConnection(con);
		}
		return resultList;
	}