When creating tables in Access, you need to select a data type for each column of data. The Short Text data type is a popular choice since it lets you enter almost any character (letter, symbol, or number). However, careful selection of data types can help you take advantage of more Access features (such as data validation and functions), and improves the accuracy of the information you’re storing. The table below gives an overview of the data types available in Access desktop databases (.accdb and .mdb).
For a comprehensive list of all the various field properties available for the various data types, see Introduction to data types and field properties.
|
Data Type |
Usage |
Size |
|---|---|---|
|
Short Text (formerly known as “Text”) |
Alphanumeric data (names, titles, etc.) |
Up to 255 characters. |
|
Long Text (formerly known as “Memo” |
Large amounts of alphanumeric data: sentences and paragraphs. See The Memo data type is now called “Long Text” for more information on the Long Text details. |
Up to about 1 gigabyte (GB), but controls to display a long text are limited to the first 64,000 characters. |
|
Number |
Numeric data. |
1, 2, 4, 8, or 16 bytes. |
|
Large Number |
Numeric data. |
8 bytes. For more information, see Using the Large Number data type. |
|
Date/Time |
Dates and times. |
8 bytes. |
|
Date/Time Extended |
Dates and times. |
Encoded string of 42 bytes For more information, see Using the Date/Time Extended data type. |
|
Currency |
Monetary data, stored with 4 decimal places of precision. |
8 bytes. |
|
AutoNumber |
Unique value generated by Access for each new record. |
4 bytes (16 bytes for ReplicationID). |
|
Yes/No |
Boolean (true/false) data; Access stores the numeric value zero (0) for false, and -1 for true. |
1 byte. |
|
OLE Object |
Pictures, graphs, or other ActiveX objects from another Windows-based application. |
Up to about 2 GB. |
|
Hyperlink |
A link address to a document or file on the Internet, on an intranet, on a local area network (LAN), or on your local computer |
Up to 8,192 (each part of a Hyperlink data type can contain up to 2048 characters). |
|
Attachment |
You can attach files such as pictures, documents, spreadsheets, or charts; each Attachment field can contain an unlimited number of attachments per record, up to the storage limit of the size of a database file. Note, the Attachment data type isn't available in MDB file formats. |
Up to about 2 GB. |
|
Calculated |
You can create an expression that uses data from one or more fields. You can designate different result data types from the expression. Note, the Calculated data type isn't available in MDB file formats. |
Dependent on the data type of the Result Type property. Short Text data type result can have up to 243 characters. Long Text, Number, Yes/No, and Date/Time should match their respective data types. |
|
Lookup Wizard |
The Lookup Wizard entry in the Data Type column in Design view is not actually a data type. When you choose this entry, a wizard starts to help you define either a simple or complex lookup field. A simple lookup field uses the contents of another table or a value list to validate the contents of a single value per row. A complex lookup field allows you to store multiple values of the same data type in each row. |
Dependent on the data type of the lookup field. |
