Profile variables
The profile_variable table drives event
processing in IBM® Predictive
Maintenance and Quality.
When an event_observation value arrives, its associated measurement_type value,
and its associated resource_type value are used to
find all of the profile_variable rows that are relevant
for that observation, according to the orchestration defined for the
event. Each of these rows indicates a calculation, which must be performed
for the event. The calculation updates rows in the kpi and profile tables
as indicated by the profile_variable. IBM Predictive Maintenance and Quality implements
a standard set of calculations, but you can add a custom calculation
and refer to it in a profile_variable row. The standard
set of calculations include the following calculations:
- Measurement of type count
- Measurement text contains count
- Interval calculation
- Measurement above limit
- Measurement below limit
- Measurement delta
These calculations are described in Profile calculations.
To be able to process some events, you must load mandatory profile variables and measurement types. For more information, see Mandatory profile variables and measurement types.
For example, a temperature event with the measurement_type value Ambient
temperature
from a device can be aggregated by defining a profile_variable
for the measurement_type Ambient temperature
with
the profile_calculation Measurement of type
and
adding a profile update for the measurement_type to the orchestration.
This causes a row to be added to the resource_kpi
table at each period for this device and profile_variable.
This row aggregates the temperature values across each period
(day). In addition, the defined profile_variable causes
a row to be added to the resource_profile table
for this device that is updated as each temperature event is processed.
Making a profile variable inactive
To make a profile variable inactive, for example, if you want to prevent a calculation from being performed, remove the profile update from the orchestration.