In the previous post, we discussed the Switch Activity, which is useful for branching the control flow based on some condition. We will discuss about the Filter Activity in this post.
The purpose of Filter Activity is to process array items based on some condition. Consider a scenario where we would like to set the value of a variable to the current array item that satisfies some business rule or condition. We can use Filter activity to design the control flow.
Let’s have a look at the example below:
As we can see in the screenshot above, the pipeline contains two activities (Filter and ForEach) with an input array which is being passed on as the inputs pipeline parameter.
Based on condition under the settings tab, the Filter Activity only selects the array items which are greater than 3:
For every array item greater than 3, the ForEach activity runs the Set Variable activity which converts the current filtered item value to string datatype and assigns it to the variable test.
As we can see from the above example, the Filter activity can be very useful while working with arrays. Without a specific activity to process array items, this would probably have to be written as SQL Code.
To learn more about ForEach activity, have a look at the previous post.
Reference: https://docs.microsoft.com/en-us/azure/data-factory/control-flow-filter-activity
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