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 Siebel Marketing User Guide > Managing Lists > Importing External Data and Creating Data Mappings > 
Creating and Modifying Data Mappings
 
The following procedure shows how to create and modify data mappings. To create and modify data mappings 
- Navigate to the Administration - Marketing screen, then the Import Mappings view. 
 - Select a mapping to modify, or create a new one.
 - Complete the fields for the mapping. The following table describes some of the fields.
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    Column Width  | 
    Number of characters. Used for fixed width files.  | 
 
    Allow Field Updates  | 
    Indicates whether the field can overwrite the value on a matching record. For example, if a matching contact is found with an existing phone number, then checking this option permits the phone number field to be updated.  | 
 
    Required Fields  | 
    Indicates if the field is required (non-nullable).  | 
 
    Ignore Field  | 
    Ignores a column during import.  | 
 
    Exact Match Column  | 
    Indicates if the field will be used as part of the exact match key in the parent business component.  | 
 
 
 
  
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