Page 49 - Database-En-V3

Field properties are a set of properties that the database developer adjusts according to the
nature of each field’s data and its purpose. He adjusts the value of the appropriate required
property or leaves it at the automatic default values found by the Access program. Field
properties are located at the bottom of the field design screen, as shown in the shaded part.
In the following figure.

We will explain each property in detail in the following table - Note: The available field properties
change according to the data type

Field size It means the storage space reserved for field values and varies
coordination depending on the data type
Input mask
If you use the AutoNumber field as a primary key or a repeat
Caption identifier, you must not set this property. Otherwise, choose a
number format that matches your needs
the virtual value
You can use this property to specify a style for all data that will be
Validation rule entered in this field. This will help ensure that all data is entered
correctly, and that it contains the required number of characters.
Validation text For instructions on creating an input mask, click in the right side of
Required the property box.
indexed
Non repeated This is the label text that appears by default for this field in the form
My reference of forms, reports, and queries. If this property is empty, the field
name is used. Any text string is allowed. An effective caption is
usually brief.

You can use this property to specify the default value that will
appear in this field each time a new record is added. For example, if
you have a date/time field where you want the date the record was
added to be recorded, you can enter "date()" (without quotes) as
the default value.

It is a rule that is set by the developer so that the value of the data
recorded in that field is checked according to that condition
(verification rule), for example, the values must be greater than 18
years and less than 60 in the worker’s age field.

An explanatory message is written for the error made by the data
entry if it does not agree with the condition (verification rule) set
for the field

This property sets whether a value is required in this field. If this
property is set to Yes, Access will not allow a new record to be added
unless a value is entered for this field.

Determines whether the field contains an index. There are three
values available:

• Yes (Non-Duplicate) Create a unique index on the field.,

• Yes (duplication is acceptable) Create a non-unique index on the
field.

42 Training unit in the field of technological information - at the Supreme Council of Universities © Intellectual property rights 2024