Types of Data Validation

Keeping records, storing, and not losing contact information is important for every enterprise. This article will explain the importance of data validation and compare its main types. 

The purpose of the data validation

Data validation is the process of checking data against various criteria. When developing any application, in most cases, the developer must process data entered by the user in the appropriate fields on the form. Unfortunately, for various reasons, the user may enter incorrect data.

It would seem that “invalid” data that does not satisfy certain restrictions can cause a program to crash. But what does it mean? Suppose an exception occurs in the program when trying to convert a string to a number if the line is not in the correct format. Of course, if the exception is not caught anywhere, this can lead to abnormal program termination. But this is an unlikely scenario. Most likely, an interceptor will work somewhere, giving the user some error message in the program or making an entry in the error log, after which the program will try to recover from the failure and continue working. Even if the validation is not performed, nothing bad will likely happen.

Effective data validation requires a risk-based approach, a full understanding of production processes, and increasing sustainability through introducing new technologies. Thus, validation is a dynamic process. This fact presents some difficulties for the regulatory authorities. Data validation can provide the following benefits:

    • a deeper understanding of the processes and, therefore, a reduction in risk while preventing problems and ensuring smooth process control;
    • reducing the cost of eliminating deficiencies;
    • reducing the risk of non-compliance with regulatory requirements.

Common types of data validation

The presence of the data validation helps prevent serious failures. It makes it easier to identify problems, but you have to pay for this in performance since additional checks increase the load on the system.

There are two types of user input validation.

      • client validation;
      • server validation.

Client-side validation is done in the browser on the client side. Typically, client-side validation logic is implemented through JavaScript scripts inside the browser. Client-side validation usually contains simple validation algorithms. It is due to the fact that the client code cannot physically access server resources (for example, a database). Therefore, the most trivial scenarios are checked on the client side (such as checking the length of a string, checking for a range, etc.).

Client validation may not be present in the application. However, if validation scripts are current on the client side, this can eliminate the need for unnecessary calls to the server in case simple validation conditions are not met.

Server-side validation works within the program code hosted on the server side. All sorts of cases are checked here, including those that have already been checked on the client side. In addition to trivial checks, more complex algorithms can work on the server side. The need to duplicate the validation of scripts that have already been validated on the client side is because client-side validations may not work if JavaScript execution is disabled in the client’s browser. In other words, client-side validation cannot guarantee successful validation of the constraints.

Thus, server validation is a necessary process that must be performed whenever user input is processed. Client validation is an optional component that saves the user from having to make unnecessary calls to the server and improves the application’s usability.