The Duplicate Value Validator can be is used to prevent duplicate value values and to enforce an input format.
Figure 1: Configuration tab Tab for Duplicate Value Validator
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Implementing validation on the Phone field "phone" to make it as:-
- Mandatory,mandatory
- unique,
- and adhere to certain a specific format using a regular expression (more on Regular Expression at http://www.regular-expressions.info/)
Figure 2: Sample
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Form
Figure 3: Sample
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Configuration
Figure 4: Sample error Error on formForm