| Smart Grid Applications Overview > Responder Overview > Implement Responder > Data Preparation > Database Schema Configuration > Assign Domains | 
To assign a domain to a particular field, it must be done by adding the domain attribute to a column tag in DatabaseSchemaConfig.xml. For example:
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                    <Column Name="CRITICAL" Caption="Critical" Domain="CRITICAL_TYPE" Represents="CriticalCustomer"/>  | 
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Virtual Domains
Responder creates some domains that are NOT defined in DatabaseSchemaConfig.xml. To use these domains, they must be assigned to a field (or column) in a table. Below are descriptions of the virtual domains automatically created by Responder.
Calculated Fields
A calculated field uses a domain value selected by the user to perform a calculation and present the result. For example, a user may select a value of 1 hour from the Time Restored Est. field. The Time Restored Est. field uses this value (1 hour) to calculate the estimated time of restoration.
In the case of a calculated field, the domain is not assigned to the field in DatabaseSchemaConfig.xml. However, the domain must be defined in DatabaseSchemaConfig.xml.
Below is a list of calculated fields in Responder:
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                 Field  | 
            
                 Domain  | 
            
                 Calculation  | 
        
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                 Time Restored Est.  | 
            
                 INCIDENT_DURATION  | 
            
                 The user-selected domain value (e.g., 1 hr) is added to the current time for an estimated time of restoration. You may modify the INCIDENT_DURATION domain. The field will use the custom values in its calculation.  |