public AmazonRedshiftNodeData withMergeWhenNotMatched(String mergeWhenNotMatched) {
        setMergeWhenNotMatched(mergeWhenNotMatched);
        return this;
    }
<p>
The action used when to detemine how a MERGE in a Redshift sink will be handled when an existing record doesn't
match a new record.
</p>

@param mergeWhenNotMatched
       The action used when to detemine how a MERGE in a Redshift sink will be handled when an existing record
       doesn't match a new record.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-glue/src/main/java/com/amazonaws/services/glue/model/AmazonRedshiftNodeData.java