Understand why a workbook refresh preserves the reader's dropdown choice

Source facts

A workbook dropdown’s default-selection field controls initial selection, not an override of later user choices. Once the user chooses values, a subsequent parameter query does not replace them with its new defaults. Default Items reruns the query and applies the defaults again. Microsoft Learn.

If refreshed results omit a previously selected value, that value is removed: selection becomes the intersection of the old selection and new results. The default-selection field is interpreted by its third-column position, and values such as false, zero, null or an empty string mean not selected. Microsoft Learn.

Applicability

Review Azure Monitor Workbooks using query-backed dropdown parameters. This behavior concerns the parameter’s selected values, not the freshness of every chart or a pinned dashboard’s saved configuration.

DSE recommendation

DSE recommends defining the intended reader experience for first load, refresh and return to defaults before modifying the parameter query. Do not treat a persisted user choice as evidence that the new query failed. If the returned item set changes, decide how downstream visuals should respond to a smaller or empty selection. Make the default-reset action discoverable in the workbook’s instructions.

Verification

Start with no user selection and confirm the default. Choose another value, change the query’s defaults in an approved test, and refresh. Then remove one chosen item from the returned list and inspect the remaining selection. Finally use Default Items and confirm the newly queried default. Record these states alongside the query column order.

Official references

Microsoft Learn: Workbook dropdown parameters.