> For the complete documentation index, see [llms.txt](https://dbi-services.gitbook.io/omrun-help/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://dbi-services.gitbook.io/omrun-help/version-4.x/configuration/using-variables/environment-variables.md).

# Environment Variables

Environment variables are used to pass parameters in to a query used by [Design Test Object](/omrun-help/version-4.x/element-overview/test-data-object.md).\
This allows to easily switch from one environment to another and pass parameterized data (e.g. Server Name, Data Source Name, Data Base Schema) to the Test Object.

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### Declare variable @DB\_Schema is Environment

In this example the value 'dev' will be passed in to the variable @DB\_Schema.

<figure><img src="/files/1FfgJo0mYBhZEMpXocz5" alt="OMrun environment grid" width="80%"><figcaption><p>OMrun environment grid</p></figcaption></figure>

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### Usage of variable @DB\_Schema in Test Object

At runtime the variable @DB\_Schema will be replaced by the value 'dev'. This mechanism enables to read data from environment specific database schemas.\
You can also use Omis variable into a parameter (@param1 - @param4) and into remark.

<figure><img src="/files/cA6rNMZCGvsBXqqXYKRj" alt="OMrun query details" width="80%"><figcaption><p>OMrun query details</p></figcaption></figure>

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### Windows environment variables

You can also use Windows system-/user variables. → (%VariableName%)

**Important**: please **restart OMrun** to get the value of the new variable loaded and accessible.