When you use the form data in an SQL query, it should be validated against SQL Injection.It is very essential to have the input to your form validated before taking the form submission data for further processing.When there are many fields in the form, the PHP validation script becomes too complex.
The validations also help in lesser server side errors.
Note: You can make web forms quickly with Simfatic Forms.
Simfatic Forms helps you to make complete, feature rich web forms and get it online quickly. This generic PHP form validator script makes it very easy to add validations to your form.
Most of cases we will use the * symbol for required field.
Validation means check the input submitted by the user.