Improving the data quality – the validation rule

In order to make your data valid and healthy when entered by a user, it is very important that you impose some constraints over the values that are being entered into the system. This is to ensure that the user cannot enter any junk values or values that don't meet your business requirements.

Salesforce.com provides a feature called the validation rule. When you apply validation rules over fields of an object, it means that the data now entered by the user must meet the parameters that you decided with the validation rule. Validation rules in Salesforce are always defined in terms of formula expressions. If the formula evaluates to true, then an error message is displayed while the record is being saved, or the record is saved to the database. Validation rules are always evaluated while creating and updating a record. Using validation rules, you can ensure your business maintains a high degree of data quality and integrity.

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