What is the difference between access verification rules and verification text?

Validation rules are used to create business rules to validate field values, while validation text is used to provide input guidance to users. Validation rules perform automatic validation through expressions or functions, limit the user input range, and display custom error messages; validation text provides prompts or instructions as input reference, does not limit the input value, and displays a default error message.

The difference between Access verification rules and verification text

Access verification rules and verification text are used in Microsoft Access Two functions that validate user input. There are some key differences in their functionality and role:

Validation Rules

• are used to create a set of business rules for field values.
• Ensure that the entered data meets specific conditions or formats.
• Automatically perform validation when the user enters data.
• Can be written using expressions, functions or SQL statements.
• Validation rules limit the range of values ​​that users can enter.
• If the validation rule fails, a custom error message will be displayed.

Validation text

• is used to provide information to the user on how to enter data.
• Tips or instructions that appear next to the field.
• Provide guidance before the user enters data.
• can be used as a reference regarding data formats, data ranges, or other input restrictions.
• Validation text does not limit the values ​​the user can enter.
• If the user enters invalid data, the Access default error message will be displayed.

Example

For example, if you want to validate the email address field, you can use the following validation rule:

<code>IsValidEmailAddress([字段名称])</code>

This will ensure that the entered The value conforms to the format of an email address.

As verification text, you can enter the following:

<code>请使用以下格式输入电子邮件地址：name@example.com</code>

This will provide the user with instructions on how to enter their email address.

Purpose

Typically, validation rules are used to enforce data integrity and ensure that entered data meets business requirements. Validation text is used to guide the user and provide information about input expectations.

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