Look-up Tables are an important feature of a good data base design. Typically they are small tables, which contain parameter codes and general values.
Altogether, the Pre-processing module uses the following Look-up Tables (sorted alphabetically). They are always linked, either online or offline. Therefore, their names are included in the Table-links.
| Table name | Notes |
|---|---|
| ADDITIONAL_RESOURCES_TYPES | |
| LU_USE_TYPE | For monthly production |
| SALINITY_CLASS | |
| WATER_USE_BILL_CAT | For water billed by WAJ |
The following LUTs are NOT linked, however their contents help to understand the codes used in various database tables:
| Table name | Notes |
|---|---|
| AGENCIES | |
| DEMAND_CENTER_TYPES | |
| END_USES | of treated wastewater |
| ISIC_CLASS_CODES | classification of industrial facilities |
| ISIC_DIVISION_CODES | |
| ISIC_GROUP_CODES | |
| MONITOR_LOCATIONS | |
| PROD_MEAS_METHOD | |
| SETT_TYPES | |
| STATION_TYPES | |
| WWTP_OWNERSHIP | |
| WWTP_TYPE |
Different from the Irrigation module the following references are not contained in look-up tables but are defined in the VBA code:
For example, the LUT for salinities looks as follows:
Table Salinity_Class TDS (total dissolved solids) in mg/l
| S_CLASS | DESCRIPTION | TDS_MIN | TDS_MAX | COMMENTS |
|---|---|---|---|---|
| 1 | Salinity Class 1 | 0 | 1000 | Good for Drinking & generally no restriction in irrgtn |
| 2 | Salinity Class 2 | 1000 | 2000 | Slight to moderate restriction on irrgtn use |
| 3 | Salinity Class 3 | 2000 | 2800 | Severe restriction on irrgtn use, only for special crops |
| 4 | Salinity Class 4 | 2800 | 50000 | Usable only after desalination |
| 0 | no Leaching | 0 | 0 | No consideration of salinity |
In the corresponding tables (particularly the STP tables), only the entry of the salinity class field [S_CLASS] is used. If salinity classes are to be redefined, it would be sufficient just to modify the Look-up table.