AutoNumber | A unique sequential (incremented by 1) number or random number assigned by Microsoft Access whenever a new record is added to a table. AutoNumber fields can't be updated. For more information, see the NewValues property. | 4 bytes (16 bytes if the FieldSize property is set to Replication ID). |
Yes/No | Yes and No values and fields that contain only one of two values (Yes/No, True/False, or On/Off). | 1 bit. |
OLE Object | An object (such as a Microsoft Excel spreadsheet, a Microsoft Word document, graphics, sounds, or other binary data) linked to or embedded in a Microsoft Access table. | Up to 1 gigabyte (limited by available disk space) |
Hyperlink | Text or combinations of text and numbers stored as text and used as a hyperlink address. A hyperlink address can have up to three parts:
displaytext — the text that appears in a field or control.
address — the path to a file (UNC path) or page (URL).
subaddress — a location within the file or page.
The easiest way to insert a hyperlink address in a field or control is to click Hyperlink on the Insert menu. | Each part of the three parts of a Hyperlink data type can contain up to 2048 characters. |
Lookup Wizard | Creates a field that allows you to choose a value from another table or from a list of values by using a list box or combo box. Clicking this option starts the Lookup Wizard, which creates a Lookup field. After you complete the wizard, Microsoft Access sets the data type based on the values selected in the wizard. | The same size as the primary key field used to perform the lookup, typically 4 bytes. |