PDI的steps：（7：Append streams）

种类：flow

id：append

描述：这个step，从2个step读取数据，不过，只处理第二个step的数据（在第一个step完成以后）。

        一般情况下，这2个step的数据行的格式是一模一样的：相同的长度，相同的字段类型，相同的索引等。

 

Important: If you don't care about the order in which the output rows occur, you can use any step to create a union of 2 or more data streams.

 

Options

Option	Description
Step name	Name of the step. Note: This name has to be unique in a single transformation.
Head hop	The name of the step from which will be read from first.
Tail hop	The name of the step from which will be read from last.