Zi primary group row 群排孜小学
The detail columns, when expanded, are displayed directly below the row that contains the primary columns of data.
具体的列，在扩展时，会直接显示在行的下面，该行包含了数据的主列。
However, each row must have a unique primary key, which is a sort of name for that particular bundle of data.
不过，每一行的主键(一种用于特定一组数据的名称)必须是唯一的。
Note that this assumes that key columns are never updated; once a row exists, it is immutably tied to its primary-key value.
注意，这假设从不更新键列；一旦一行存在了，它的主键值就不变了。
应用推荐