Add a measure

You can create a measure by using the FAB button.

Add a measure

1. Open the AVEVA BI Gateway Model Builder.

2. Click the Add icon in the Fast Action Buttons menu and then click the Measure icon. A new measure is added in the AVEVA BI Gateway model with a default name and the Measure editor appears in the right pane.

3. Click the General tab and do the following:

   1. In the Name box, type a new name for the measure. The measure name must be unique and can have a maximum length of 32 characters. The measure name can contain only a-z, A-Z, 0-9, underscore (_), dollar ($), and hash (#) characters. The first character must not be a dollar sign ($). The measure name must contain at least one letter.

   2. In the Description box, type a description for the measure. The description can contain a maximum of 256 characters.

4. Click Save.

Configure data collection details for a measure

You have to provide a data collection start date and time and optionally an offset time for a measure. You must provide a refresh rate and update period for the measure. The measure is first populated on the start date and time that you specify. Thereafter, the measure data is refreshed as per the configured refresh rate and the update period.

You must provide an update period to define a time interval for which measure data has to be refreshed during the measure refresh.

For example, if you specify a refresh rate of one hour and an update period of one day, then the system refreshes the measure data for the past day after every one hour.

The system also triggers a check on the configured refresh rate to verify if there is a measure period or dimension time-slices identified since the last refresh. New measure values are calculated for each time-slice defined by measure period and time-slicing dimensions and the values are stored in the measure table.

For more information about measure period and dimension time-slicing, see Configure a Measure Period and "Configuring Time-Slicing for a Dimension".

You have to provide a measure data collection start date and time that is before or equal to the measure deployment date. Upon deployment, the process of computing measure calculations for each time-slice between the data collection start time and the current time is called measure backfilling. Thereafter, new measure values are calculated as per the configured refresh rate and update period.

You can also provide an offset time to delay the refresh execution. Using an offset time can be useful to ensure that transactions at the data source have completed prior to the extraction of data for the measure.

Configure a data collection start date, refresh rate, update period, and offset time for a measure

5. In the Refresh rate area, specify a refresh rate and offset time for the measure. Do the following:

   

   1. In the Interval list, click a refresh rate for the measure.

   2. In the Unit list, click a unit of time for the refresh rate. You can provide a minimum refresh rate of one minute and a maximum refresh rate of 366 days. The default refresh rate is one day.

   3. In the Offset (minutes) list, click an offset time in minutes. The offset time is used to delay the scheduled refresh of the measure. You can provide an offset time of maximum 59 minutes. The default offset time is zero minutes.

6. In the Update period area, do the following:

   

   1. In the Interval list, click the required update period for the measure.

   2. In the Unit list, click the required unit of time for the update period. You can provide a minimum update period of one millisecond and a maximum update period of 366 days. The default update period is one day.Be sure that the update period is equal to or more than the refresh rate.

7. In the Data backfill area, specify a data collection start date and time. In the Data collection start list, click the start date and time to collect data from the data sources and populate the measure. You must provide a start date and time prior to the measure deployment date. The default start date and time is 12:00:000 A.M. on the date of measure creation.

8. Click Save.

Configure a measure period

You can configure a measure period, which will force the computation of the measure calculations at the specified period. For example, a Measure object configured with a measure period of one hour stores calculations in the measure table for every hour since the data collection start time.

For each measure calculation, you must provide a source data item field mapping that is used to calculate period for measure calculation.

Because measure records are described by a time-slice, a Measure object must at least have one time context defined either by a measure period, and/or time-slicing dimensions. If you do not provide a measure period or do not relate the measure to a time-slicing dimension, then after saving the measure the state of the measure changes to "Warning" and measure values are not calculated.

Configure a measure period

9. Select the Measure period check box.

   

10. In the Interval list, type or click a period for measure calculation.

11. In the Unit list, click the unit of time for the period.

    You can provide a minimum period of one millisecond and a maximum period of 366 days. The default measure period is one hour.

12. Click Save.

Assign measure to a file group

Assign the measure to a pre-configured file group, do the following:

13. Select the Override SQL Server default file group check box.

    

14. In the File group name box, type the name of the pre-configured file group to which you want to associate the measure. The file group name can contain a maximum of 128 characters.

    • File groups help support database growth and performance by storing data in different files.

    • You can associate a measure to a SQL Server file group. The measure table is created and the measure data is stored on the server file group that you specify.

    • Before associating a measure to a file group, you must create and configure the file group in the SQL Server where the data store resides.

    • If you do not associate a measure to a file group, then the measure table is created and the measure data is stored in the default file group called "Primary".

    • Associating measures to different file groups helps distribute the data, thereby enhancing the performance.

      For more information about creating file groups, see the Microsoft SQL Server documentation.

      Note: If the file group that you specify is not available in the SQL Server, then the system assigns the measure to the default file group.

15. To associate the measure to the default file group, clear the Override SQL Server default file group check box.