Use the Filter transformation to filter out rows in a mapping. As an active transformation, the Filter transformation may change the number of rows passed through it. The Filter transformation allows rows that meet the specified filter condition to pass through. It drops rows that do not meet the condition. You can filter data based on one or more conditions. The Filter transformation is an active transformation.
A filter condition returns TRUE or FALSE for each row that the Integration Service evaluates, depending on whether a row meets the specified condition. For each row that returns TRUE, the Integration Services pass through the transformation. For each row that returns FALSE, the Integration Service drops and writes a message to the session log.
The following mapping passes the rows from a human resources table that contains employee data through a Filter transformation. The filter allows rows through for employees that make salaries of $30,000 or higher.
You cannot concatenate ports from more than one transformation into the Filter transformation. The input ports for the filter must come from a single transformation.
Place the Filter transformation as close to the sources in the mapping as possible to maximize session performance. Rather than passing rows you plan to discard through the mapping, you can filter out unwanted data early in the flow of data from sources to targets.