# Declare a global workbook time parameter before synchronizing chart brushing

> Make the scope of an interactive time selection explicit.

- Canonical URL: https://update.dsesecurity.com/updates/dse-20260917-106-declare-a-global-workbook-time-parameter-before-synchronizing-chart-brushing/
- Publisher: Detection Systems & Engineering (DSE Security)
- Author: DSE Security Editorial Team
- Published: 2026-09-17T16:33:14+00:00
- Modified: 2026-09-17T16:42:35+00:00
- Last reviewed by DSE: 2026-09-17
- Resource type: Guide
- DSE priority: Information
- Topics: Cybersecurity, IT
- Reading time: 1 minutes

## What you need to know

Make the scope of an interactive time selection explicit.

## Potentially affected

Use this review for a workbook intended to synchronize time selection across multiple charts. Identify which controls should share the value and which should remain independent. Review the parameter dependencies before making an existing local parameter global.

## DSE recommendation

DSE recommends declaring the shared parameter once and documenting which chart inputs and outputs use it.

## Article

## Source facts

Microsoft says a global workbook parameter must be declared in a parameters step using the global option. Selections, brushing, links, buttons and tabs can update an existing global parameter, but cannot create one. The declaration determines whether those interactions can update a shared value. [Microsoft Learn](https://learn.microsoft.com/en-us/azure/azure-monitor/visualize/workbooks-parameters).

## Applicability

Use this review for a workbook intended to synchronize time selection across multiple charts. Identify which controls should share the value and which should remain independent. Review the parameter dependencies before making an existing local parameter global.

## DSE recommendation

DSE recommends declaring the shared parameter once and documenting which chart inputs and outputs use it. Test a copied workbook before changing the shared report. Keep unrelated filters local, and have a reviewer inspect dependencies for unintended cycles. Label the active time selection so readers can understand the scope of the displayed evidence.

## Verification

Brush a time interval in each participating chart and confirm that all intended charts update, including those above the changed control. Verify that intentionally independent charts retain their own scope. Reload the workbook and repeat the interaction from its default state. Preserve the tested parameter declaration and bindings with the workbook version used for the report.

## Official references

[Microsoft Learn: Create workbook parameters](https://learn.microsoft.com/en-us/azure/azure-monitor/visualize/workbooks-parameters).

## Primary reference

- Name: Create workbook parameters - Azure Monitor | Microsoft Learn
- Authority: Microsoft Learn
- URL: https://learn.microsoft.com/en-us/azure/azure-monitor/visualize/workbooks-parameters
- Source publication date: Not stated by the source

## Citation and use

Preferred citation: “Declare a global workbook time parameter before synchronizing chart brushing,” DSE Security, https://update.dsesecurity.com/updates/dse-20260917-106-declare-a-global-workbook-time-parameter-before-synchronizing-chart-brushing/
Publishing principles: https://update.dsesecurity.com/updates/dse-updates-editorial-methodology/
Usage and citation policy: https://update.dsesecurity.com/usage/
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