java getString
今天读到一段从oracle中读代码的代码,忘了getString(1)什么意思了,特意查了一下学习了一下。
这是文档中的解释:要注意1就是第一列
String getString(int columnIndex) throws SQLException Retrieves the value of the designated column in the current row of this ResultSet object as a String in the Java programming language. Parameters: columnIndex - the first column is 1, the second is 2, ... Returns: the column value; if the value is SQL NULL, the value returned is null Throws: SQLException - if the columnIndex is not valid; if a database access error occurs or this method is called on a closed result set
- 以 Java 编程语言中
String
的形式获取此ResultSet
对象的当前行中指定列的值 - 参数:
columnIndex
- 第一个列是 1,第二个列是 2,……- 返回:
- 列值;如果值为 SQL
NULL
,则返回值为null
- 抛出:
SQLException
- 如果 columnIndex 无效;如果发生数据库访问错误或在已关闭的结果集上调用此方法
程序片段:
…… String name,addr; Customer cust; Connection con = obtainConnection(); Statement stmt = con.createStatement(); ResultSet result = stmt.executeQuery( "SELECT cust_name, address FROM Customer " + "WHERE ssn=" + "'" + id + "'"); if (result.next()) { name = result.getString(1); addr = result.getString(2); cust = new Customer(id,name,addr); } else { throw new BrokerException("用户" + id + "的信息没找到 :("); } return cust;