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This selects four bytes of the NATIONAL_ID, starting in column 6. You may type in the field name (don't forget the prefix) or press the Add Field link to search for the field. Press OK when you are done.
Note Remember to use the field/expression in your report.
An example of substring:
An example of Month and Day in the report as Birthdate: Note: Do not forget to use this as field. Click use as field option from 'Expression' page.
Date Substring:
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