What is the calculated data type? Explain why some database designers say this is an inappropriate field type. The Yes/No data type can use custom formats containing up to three sections. Explain the three parts. Describe the differences between a Filter by Form and Filter by Selection. Why is the AutoNumber data type ideal to use as a primary key? What types of documents can you attach to
records in your database? Why should you be cautious when using an Attachment field property?
What will be an ideal response?
A Calculated data type allows you to display the results of a calculation in a read-only field. The calculation must refer to other fields in the same table.
Some database designers say that adding calculated fields in a table violates normalization rules. In some situations, they are right. However, sometimes it is acceptable to break the rules. For example, if you know that you will need the calculation in every object—query, form, or report—based on the table and you know that the expression will not change over time, then use this data type. Additionally, if having the calculation in the table makes your data easier to understand, then it is an acceptable data type to use.
The first section has no effect on the Yes/No data type. However, a semicolon is required and used as a placeholder. The second section contains the text to display in place of Yes, True, or On values. The third section contains the text to display in place of No, False, or Off values.
The Filter by Form method creates a blank table for the selected table. This blank table contains all the fields of the table with a list for each field. Each list contains all the unique values of records for each field. This method allows you to select the field value easily for which you want to filter the table records.
In some cases, the Filter by Selection method may not be very helpful as you may need extra efforts to find your initial value. This displays only the rows in a table containing a value that matches a selected value in a row by filtering the Datasheet view.
Also known as a surrogate key, the AutoNumber data type is an ideal primary key because it is short, numeric, and never changes.
You can attach images, spreadsheet files, documents, charts, and other types of supported files to the records in your database, much like you attach files to an e-mail message. Access allows you to view and edit the attached files, depending on how the database designer configures the Attachment field properties. Where you need to use caution is that attachments do increase the size of your database, and developers need to ensure that attachments will not use too much storage space.
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The higher a sound's bit depth, the higher its fidelity.
Answer the following statement true (T) or false (F)