(異常)java.sql.SQLException: 未呼叫 ResultSet.next
阿新 • • 發佈:2018-12-09
當用ResultSet接收來自資料庫查詢的結果集時,即使結果集只有一條資料,也需要用到resultSet.next()函式移動遊標獲取資料。
錯誤程式碼:
conn = DriverManager.getConnection(url, "briup", "briup"); String sql = "select password from e_customer where name=?"; pre = conn.prepareStatement(sql); pre.setString(1, username); resultSet = pre.executeQuery(); String passwd = null ; passwd= resultSet.getString(1); if(passwd.equals(password)&&password!=null) { flag = true;
修改後:
conn = DriverManager.getConnection(url, "briup", "briup"); String sql = "select password from e_customer where name=?"; pre = conn.prepareStatement(sql); pre.setString(1, username); resultSet = pre.executeQuery(); String passwd = null ; while (resultSet.next()) { passwd= resultSet.getString(1); if(passwd.equals(password)&&password!=null) { flag = true; }