What is a function of a filter expression in data list controls?

The function of a filter expression in data list controls is to filter customers based on selected criteria. This means that when a filter expression is applied, only the records that meet specific criteria set by the user are displayed, making it easier to analyze or review relevant information.

For example, if a user wants to see only customers from a certain region or those who have made a purchase in the last month, the filter expression allows the data list to be narrowed down to just those entries. This dynamic filtering helps users focus on pertinent data without altering the underlying database or table, ensuring that the entire dataset remains intact while providing flexibility in data analysis.

Other options, such as displaying all customers regardless of selection, summarizing order details, or removing unwanted data permanently, do not accurately describe the purpose of a filter expression. Displaying all customers does not serve the purpose of filtering, and summarizing order details or permanently removing data relates to different functionalities that are separate from filtering operations.