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The Live Date Series Data report may be used to chart Live data together with non-Live data in the same Time Series Chart widget.

 

The Live Data Deriver and Data Computation agents can perform calculations/post-processing of the data.  The calculated/post-processed data can then be charted in the Time Series Chart widget, but they add data to DT_LOGGER_DATUM.

 

An alternative is to use the Live Historical Chart widget, with a table-valued SQL function as the data source. This allows non-Live data to be charted together with Live data, as well as calculations/post-processing to be performed on Live data before it is charted, without adding the data to DT_LOGGER_DATUM.

 

How to Create a Series with an SQL Function as a Data Source

 

1.Create a new DT_LOGGER_SERIES row ('series'), e.g, using EQuIS Professional.

2.Set series_function for this new series to: sql_fn.

3.Set series_function_info for this new series to the name of the function that returns the data, e.g., equis.fn_get_measure_datum, or equis.Live_Pa_mH2O.

 

The SQL function (in Step 3) must accept the following two parameters:

1.INT – The LOGGER_SERIES_ID of the series that is added to the Historical Chart widget (i.e., the series that is created in Step 1).

2.DATETIME – The Start Date that is selected in the Historical Chart widget, when adding the series.

 

The SQL function must also return a TABLE with two columns: DATUM_UTC_DT (DATETIME; UTC), and DATUM_VALUE (REAL), sorted ascending by DATUM_UTC_DT.

 

 

Examples

1.Charting Non-Live Data

2.Charting Calculated Live Data