What is the correct action when using wildcards for the 'Omit' field?

When using wildcards for the 'Omit' field in Qlik Sense, the correct action is to leave the field empty. Leaving the field empty allows for the omission of all results that match the wildcard criteria specified. This approach effectively filters out unwanted data without needing to specify exact values, enhancing data management flexibility.

In this context, using wildcards means leveraging characters like '*' to represent any number of characters or '?' to replace a single character; therefore, when combined with an empty field, the wildcard directs Qlik Sense to consider and process the results to be omitted based on the defined pattern. This technique can be particularly useful when dealing with data sets that need dynamic filtering based on variable criteria.

The other answer choices indicate actions that either suggest limitations or misunderstandings of the wildcard function. Specifically, asserting that wildcards must be used on key fields restricts their flexibility, while stating they can be used on any field does not fully capture the specific nature of the omission process. Suggesting they create a second instance of data misinterprets the intended functionality of variant data filtering, and adding that they may leave the field empty does not appropriately represent the efficiency and intention behind their use in omitting data.