Part I: Access Building Blocks
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OLE Object
The OLE Object field stores OLE data, highly specialized binary objects such as Microsoft Word
documents, Excel spreadsheets, sound or video clips, and images. The OLE object is created by an
application that Windows recognizes as an OLE Server, and can be linked to the parent application
or embedded in the Access table. OLE objects can only be displayed in bound object frames in
Access forms and reports. OLE objects can be as large as 1GB or more in size. OLE fields can’t be
indexed.Attachment
The Attachment data type was introduced Access 2007. In fact, the Attachment data type is
one of the reasons Microsoft changed the format of the Access data file. The older .mdb format is
unable to accommodate attachments.The Attachment data type is relatively complex, compared to the other type of Access fields, and
requires a special type of control when displayed on Access forms. For details on this interesting
type of field, turn to “Understanding Attachment Fields,” later in this chapter.Hyperlink data type
The Hyperlink data type field holds combinations of text and numbers stored as text and used
as a hyperlink address. It can have up to three parts:l The text that appears in a control (usually underlined).l (^) The Internet address — the path to a file or Web page.
l Any sub-address within the file or page. An example of a sub-address is a picture on a
Web page. Each part of the hyperlink’s address is separated by the pound sign (#).
Access hyperlinks can even point to forms and reports in other Access databases. This means that
you can use a hyperlink to open a form or report in an external Access database and display the
form or report on the user’s computer.
Lookup Wizard
The Lookup Wizard data type inserts a field that enables the end user to choose a value from
another table or from the results of a SQL statement. The values may also be presented as a combo
box or list box. At design time, the Lookup Wizard leads the developer through the process of
defining the lookup characteristics when this data is assigned to a field.
As you drag an item from the Lookup Wizard field list, a combo box or list box is automatically
created on the form. The list box or combo box also appears on a query data sheet that contains
the field.
Entering a field description
The field description is completely optional; you use it only to help you remember a field’s uses or to
let another developer understand the field’s purpose. Often, you don’t use the Description column at
all, or you use it only for fields whose purpose is not obvious. If you enter a field description, it
appears in the status bar whenever you use that field in Access — in the datasheet or in a form. The