FIELD_SOURCE is a fixed lexicon which is used to identify the field source
X_FIELD_SOURCE is a fixed lexicon with the following values:
| Saved Value | Displayed Value |
|---|---|
| 00 | Not Specified |
| 01 | Constant |
| 02 | Data Base Column |
| 03 | Statistic |
| 04 | Pay Component |
| 05 | Element |
| 06 | IDGV Variable |
