Compare Events function

The Compare Events function returns events that meet specified criteria in a PI AF database. Use the Compare Events function to view events in a flat format. The function returns one event per row, but can return attributes from related events in that same row. Specifically, to facilitate event comparison, the function can return attributes from child events or parent events in the same row as the returned event.

Use the fields at the top of the Compare Events task pane to specify which PI AF events you want to retrieve. As you specify the search criteria for events, the task pane Preview list shows the matching events. Modify the criteria to adjust the matching events before inserting the function array into the worksheet. Use the fields at the bottom of the task pane to specify the columns to include and the position of the inserted function array.

For more details, see the following topics:

• Events in worksheets

  PI DataLink can display data from PI AF events with either the Explore Events function or the Compare Events function.

• Compare events by including child events

  Follow this procedure to use the Compare Events function to compare events that have child events with the same names.

• Compare events by including parent events

  Follow this procedure to use the Compare Events function to compare events from matching hierarchies when child events have different names.

• Compare Events task-pane reference

  The fields in the task pane let you specify the events to retrieve and the columns and data to return to the worksheet.

• Path notation for Compare Events function

  Use specific path notation in attribute names to designate the location in the event hierarchy.

• Reserved attribute names

  To avoid conflicts with automatically generated attributes, do not define events that use reserved attribute names.

• Compare Events example

  Set the Compare Events function inputs to compare temperature-alert events.

• Manage PI DataLink settings from Excel

  Use the Settings window to set the maximum number of events that the function returns.