Two fields are used to identify water quality variables in the database:
lab_parameter - original codes
in historical data files provided by lab
Parameter codes have been assigned for variables that have been routinely analyzed under the AMP. The corresponding records (~90% of total) have been screened for outliers, are retrieved in most of the supplied queries, and supported by the application software (load calcs, trend analysis, etc.)
| Variable Class | Primary | Secondary |
| Description | nutrients, inorganics, organics, field data | trace metals,trace organics, not routinely measured under AMP |
| Level Screening | sample identifiers, parameter codes, outliers | sample identifiers |
| Included in Supplied Queries | master, master_filtered, etc | master only |
| Statistical Analysis Supported | yes (trend analysis, outliers, load calcs) | no |
| Registered in Table(s) | parameters & lab_parameters | lab_parameters |
| Data in Results Table | yes | yes |
| Percent of Total Records | ~90% | ~10% |
| Number of Codes | 71 | 302 |
To promote a lab_parameter from secondary to primary:
Define a new Parameter code in the
Parameter table (code, description, units, etc).
Enter that same code in the
Parameter field of the Lab_Parameters table
for each record with the corresponding lab_parameter code. For example,
the parameter code 'DO-F' is entered in records with lab_parameter codes of
'DO-Field', 'DO_F', 'DO_field', etc.
To demote a lab_parameter from
primary to secondary:
Delete the parameter field entry in the Lab_Parameters
table.
Delete the record in the Parameters table (optional).The parameter code can remain in the Parameters table, but the data will not be retrieved by filtered queries.
Additional Notes
Entering 'Y' (or any character) in the 'Exclude' field of the Lab_Parameters table will have exclude records from the master query.
Similarly, entering 'Y' (or any character) in the 'Exclude' field of the Parameters table will have the effect of excluding records from the master_filtered query .
These options can be invoked to simplify query output and focus on subsets of parameters.
The 'parameter_group' field in the parameter table can also be used to classify the parameters into groups and subsequently restrict query output.
Warnings
The same lab_parameter code cannot be used if the reporting units change, as defined in the lab data files. If this occurs, the lab_parameter codes must be modified.
Similarly, distinct lab_parameter codes must be used if it is important to distinguish between different analytical procedures, as indicated in the methods field of the lab database.
