Applies to:
history
History Service
The History service is used to fetch tag data from a process histortian. i.e. MOPS Historian. The
history service allow fetching with aggregated value using differenbt agrregation types.
Properties
| Property Name |
Description |
| Name |
Identity of the component |
| Mode |
Able to retain multiple tags or just the latest |
Actions
Fetch Tag
| Name |
Description |
| Tag Name |
Identifier to tag in the historian db |
| From Date |
From date for period of data to fetch |
| To Date |
To date for period of data to fetch |
| Resolution |
Aggregation period |
| Interpolation method |
The interpolation of the dataset |
| Aggregate type |
Options if interpolation method is set to aggregate |
| Number of values |
Maximum amount of values to fetch |
| Status |
Filter the result by status |
| Align |
Which period edge to align the timestamps to |
| Edges |
Which edges to include in the interpolation |
| Extend |
Whether to extend interpolated periods into the past or future if no data |
| Bounds |
Include one extra value on either side of starttime/endtime |
| Elements |
Only fetch the elements(s) specified (only for profiles) |
Interpolation method
| Name |
Description |
| None |
No interpolation |
| Aggregate |
Process the data as aggregates according to the Aggregate table below |
| Exacttime |
Interval RAW points are only returned if the timestamp is EXACTLY on the interval |
| Extcenter |
Interval values are calculated as averages. Missing periods are extrapolated from the average value forward. |
| Extleft |
Interval values are calculated as averages. Missing periods are extrapolated from the last value backwards |
| Extright |
Interval values are calculated as averages. Missing periods are extrapolated from the last value forward. |
| Interpolated |
Interval points are interpolated from the two bounding points. Interpolation is either linear or flat depending on Pointtype |
| Weighted |
Default. Data rows are calculated based on weighted averages for each period. The weighted average is calculated according to whether the Pointtype is STEP or ANALOG. Missing intervals are interpolated depending on the Pointtype. |
Aggregate type
If Interpolation method is set to Aggregate this parameter is used. Some aggregate types are
mutually exclusive (meaning that not all aggregate types can be combined). The aggregate types are
grouped in order how to be combined and the type of value they return E.g. aggregatetype = average,
count. Within the interval starttime-endtime an average and the number of values is calculated. The
result is shown in the application from which you have made the request. The aggregate works within
the sample interval, starttime to endtime. The sample interval could be divided into resample
intervals if resolution is set. Eg Starttime=2004-08-01 06:00, Endtime=2004-08-02 06:00,
Resolution=1h. The sample interval is 1 day and the resample interval is 1 hour, there are 24
resample intervals. (If resolution is not set the resample interval is 1 day.)
| Group |
Name |
Description |
|
None |
|
| Other |
|
Aggregate types in the group Other could be combined with all other aggregate types. |
|
Count |
Retrieve the number of RAW values over the resample interval. |
|
Interval |
Return the resample Interval length |
| Raw Data |
|
Aggregate types in the group Raw data could be combined within the group and with aggregate types in the group Other |
|
Delta |
Retrieve the difference between the FIRST and LAST RAW value in the resample interval |
|
First |
Retrieve the first (earliest) RAW value in the resample interval. |
|
Last |
Retrieve the last (latest) RAW value in the resample interval. |
|
Maximum |
Retrieve the maximum weighted value over the resample interval. |
|
Minimum |
Retrieve the minimum weighted value over the resample interval. |
|
Pointaverage |
Retrieve the average data over the resample interval. The average is a simple SUM/Numpoints for RAW data. |
|
Pointmaximum |
Retrieve the maximum RAW value in the resample interval. |
|
Pointminimum |
Retrieve the minimum RAW value in the resample interval. |
|
Pointtotal |
SUM of all RAW points in the resample interval. |
|
Range |
Retrieve the difference between the minimum and maximum RAW value over the sample interval. |
|
Regconst |
Retrieve the intercept of the regression line over the resample interval of the RAW data. This is the value of the regression line at the start of the interval. |
|
Regdev |
Retrieve the standard deviation of the regression line of the RAW data over the resample interval. |
|
Regslope |
Retrieve the slope of the regression line over the resample interval of the RAW data |
|
Stdev |
Retrieve the standard deviation of the RAW values over the resample interval. |
|
Totalx2 |
Retrieve the total of the RAW value **2 |
|
Variance |
Retrieve the variance of the RAW data over the sample interval. |
| Pseudoaggregate |
|
Aggregate types in the group Pseudoaggregate could be combined within the group and with aggregate types in the group Other. |
|
Average |
This is a ‘Pseudo’ Aggregate. This will translate into the correct ?AVERAGE depending on the tags Pointtype. ANALOG=TIMEAVERAGE STEP=STEPTIMEAVERAGE DISCRETE=POINTAVERAGE |
|
Total |
This is a ‘Pseudo’ Aggregate. This will translate into the correct ?TOTAL depending on the tags Pointtype. ANALOG=TIMETOTAL STEP=STEPTIMETOTAL DISCRETE=POINTTOTAL |
| Step |
|
Aggregate types in the group Step could be combined within the group and with aggregate types in the group Other. |
|
Steptimeaverage |
Retrieve the time weighted average data over the resample interval. The value is calculated assuming continuously STEP analog/digital values. |
|
Steptimetotal |
Retrieve the totalized value (time integral) of the data over the resample interval. The integral is calculated assuming STEP varying analog/digital values. Integral time unit is per Hour. |
| Time |
|
Aggregate types in the group Time could be combined within the group and with aggregate types in the group Other. |
|
Timeaverage |
Retrieve the time weighted average data over the resample interval. The average is calculated assuming continuously varying analog values. |
|
Timetotal |
Retrieve the totalized value (time integral) of the data over the resample interval. The integral is calculated assuming continuously varying analog values. Integral time unit is per Hour. |
| Interpolative |
|
Aggregate types in the group Interpolative could NOT be combined with any other aggregate type except aggregate types in the group Other |
|
End |
Interpolate the value at the end of the resample interval. The interpolation is done depending on the tags Pointtype |
|
Start |
Interpolate the value at the beginning of the resample interval. The interpolation is done depending on the tags Pointtype |
| Actualtime |
|
Aggregate types in the group Actualtime could NOT be combined with any other aggregate type except aggregate types in the group Other |
|
Maximumactualtime |
Retrieve the maximum RAW value in the resample interval and the timestamp of the maximum value if requested alone. |
|
Minimumactualtime |
Retrieve the minimum RAW value in the resample interval and the timestamp of the minimum value if requested alone. |
Events
| Name |
Description |
Event Information |
| Fetched |
Data Loaded |
{“tagName”:""} |
Output Data
| Name |
Description |
| value |
The value of the input field in the text field |
Value Data
| Name |
Description |
| source |
The source of the tag |
| name |
Name of the tag |
| description |
The description of the tag |
| egu |
Engineering unit |
| datatype |
Historian data type |
| group |
Historian data group |
| trended |
TRue if tag is trended |
| attributes |
The attributs of the tag |
| data |
Data points of the tag |
| topic |
The topic used for Eventbroker |
