17.2 The Data Hierarchy(Cont) o Fields(字段或数据项 °由字符组成 °代表一定的含义 o Example 姓名,颜色等等 ° Records(记录) °由多个字段组成 °C++中表现为:类 o Example o An employee's record might include id#, name, address, etc 记录的关键字: A record key is a field unique to each record 0 2018, SEU. All rights reserved. 7© 2009, SEU. All rights reserved. © 2018, SEU. All rights reserved. 7 17.2 The Data Hierarchy (Cont.) Fields(字段或数据项) 由字符组成 代表一定的含义 Example 姓名，颜色等等 Records(记录) 由多个字段组成 C++中表现为：类 Example An employee’s record might include id#, name, address, etc. 记录的关键字：A record key is a field unique to each record