Seems like Edit Schema is just editing the temporary schema (WKF). Just
like editing schema source in configuration, but instead it's on the
fly. So, an expression field can be added to the WKF to be used further
downstream. Since it is just an expression to the temp schema, it
doesn't create a database column and no data being written. In my
impression, WKF creation of an enrichment should factor in at least the
largest column size involved in the formula/expression. This is not
ideal, but mayb...