For example, let’s say you have an object that represents the delivery of an advertisement called AdEvent. Let’s assume an AdEvent has three relevant properties: accountName, campaignName, and adName. If you wanted to summarize by all 3 properties, you would set your groupBy property as follows:
groupBy=accountName,campaignName,adName
This causes the summarizer to only consider two AdEvents as matching if all three of the properties are the same. If you want to summarize by campaigns instead (regardless of accounts or ads), then you would set the groupBy property to:
groupBy=campaignName
This causes the summarizer to consider two AdEvents as matching if their campaignNames are equal. You can have more than one summarizer listening for the same data items. So if you wanted to combine the above two summarization examples, you would configure two summarizers and have them both listen for the same data items.
