public void setUpsert(Boolean upsert) {
        this.upsert = upsert;
    }
<p>
The action used on Redshift sinks when doing an APPEND.
</p>

@param upsert
       The action used on Redshift sinks when doing an APPEND.
aws-java-sdk-glue/src/main/java/com/amazonaws/services/glue/model/AmazonRedshiftNodeData.java