Removing fields with the Filter node

Whereas the Select node works on records, the Filter node works on fields. The Filter node discards fields, renames fields, and maps fields from one source node to another. Often, a Filter node is used to remove fields that have one of two potential problems:

• A large proportion of missing records
• All (or almost all) records having the same value

In our case, we have two fields that have a large portion of missing values, therefore we will remove these fields:

1. Place a Filter node from the Field Ops palette to the right of the Append node.
2. Connect the Append node to the Filter node.
3. Right-click the Filter node, then click Edit.

The Filter node (or Filter tab of a source node) allows data to pass through it and has two main functions:

• Removing unwanted fields
• Renaming fields

The left column of a Filter node lists the field names as the data enters the node. The right column of a Filter node shows the field names as the data leaves the node. By default, the lists are...