public DataSourceIntrospectionModelIndex getPrimaryKey() {
        return this.primaryKey;
    }
<p>
The primary key stored as a <code>DataSourceIntrospectionModelIndex</code> object.
</p>

@return The primary key stored as a <code>DataSourceIntrospectionModelIndex</code> object.
aws-java-sdk-appsync/src/main/java/com/amazonaws/services/appsync/model/DataSourceIntrospectionModel.java