Using SelectFromCollection to choose which dataset to keep

Use the SelectFromCollection transform to convert a collection of DynamicFrames into a single DynamicFrame.

To add a SelectFromCollection transform node to your job diagram

1. (Optional) Open the Resource panel and then choose SelectFromCollection to add a new transform to your job diagram, if needed.

2. On the Node properties tab, enter a name for the node in the job diagram. If a node parent is not already selected, then choose a node from the Node parents list to use as the input source for the transform.

3. Choose the Transform tab.

4. Under the heading Frame index, choose the array index number that corresponds to the DynamicFrame you want to select from the collection of DynamicFrames.

   For example, if the parent node for this transform is a SplitFields transform, on the Output schema tab of that node you can see the schema for each DynamicFrame. If you want to keep the DynamicFrame associated with the schema for Output 2, you would select 1 for the value of Frame index, which is the second value in the list.

   Only the DynamicFrame that you choose is included in the output.

5. (Optional) After configuring the transform node properties, you can view the modified schema for your data by choosing the Output schema tab in the node details panel. The first time you choose this tab for any node in your job, you are prompted to provide an IAM role to access the data. If you have not specified an IAM role on the Job details tab, you are prompted to enter an IAM role here.

6. (Optional) After configuring the node properties and transform properties, you can preview the modified dataset by choosing the Data preview tab in the node details panel. The first time you choose this tab for any node in your job, you are prompted to provide an IAM role to access the data. There is a cost associated with using this feature, and billing starts as soon as you provide an IAM role.