public boolean addNewColumn(String tableName, String columnName,
			String columnType) {
		// Ƿ
		String sql = "select * from " + tableName + " where 1=2;";
		ResultSet rs;
		try {
			rs = executeSelectQuery(sql);
			ResultSetMetaData rsmb = rs.getMetaData();
			boolean flag = false;// Ĭв
			for (int i = 0; i < rsmb.getColumnCount(); i++) {
				if (rsmb.getColumnName(i + 1).toString().equals(columnName)) {
					flag = true;
					break;
				}
			}
			rs.close();
			if (!flag) {// в
				sql = "alter table " + tableName + " add " + columnName + " "
						+ columnType;
				if (executeAlterQuery(sql)) {
					System.out.println("ɹУ" + columnName);
					return true;
				} else {
					System.out.println(" " + columnName + " ʧ");
					return false;
				}
			}
			else
			{
				System.out.println(" " + columnName + " Ѿڣִк.");
			}
			return true;
		} catch (SQLException e) {
			e.printStackTrace();
			return false;
		}
	}