Using the Large Number data type

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The Large Number data type stores a non-monetary, numeric value and is compatible with the SQL_BIGINT data type in ODBC. Use this data type to efficiently calculate large numbers.

Large Number data type range

You can add it as a field to an Access table. You can also link to or import from databases with a corresponding data type, such as the SQL Server bigint data type. To add the Large Number data type, you need Access 2016 (16.0.7812 or later).

In this article

Adding a Large Number field to a table

Linking to or importing from an external database with SQL_BIGINT data type support

Understanding the impact of Large Number data type support

Backward Compatibility Considerations

Adding a Large Number field to a table

The Large Number data type (eight bytes) gives you a much greater range for calculation than the Number data type (four bytes). For example, the Number data type has a range of -2^31 to 2^31-1 but the Large Number data type has a range of -2^63 to 2^63-1. For more information, see Introduction to data types and field properties.

When you add a Large Number field to a table and save the table design, you have effectively enabled the Large Number data type, and the database is no longer compatible with previous Access versions. Before you save your table design, you are notified with a warning message in case you need to keep the database compatible. For more information, see Backward Compatibility Considerations.

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Understanding the impact of Large Number data type support

Before you start using the Large Number data type, It’s very important that you understand the impact it could have on your Access databases.

Stamping of Access 2007-2016 file format (.accdb) to Access 2016

To summarize, there are two ways you can enable support of the Large Number data type: when you add a field to a local table with the Large Number data type and when you set the Support Bigint Data Type for Linked/Imported Tables Access option. However you enable support of the Large Number data type, it is a permanent change to the database that cannot be reversed. In each case, Access displays a warning message before you make the change.

Behind the scenes, enabling the Large Number data type stamps the Access 2007-2016 file format (.accdb) to Access 2016. Stamping a database file format means you have made a specific change to the file format, the database version is increased, but otherwise the file format remains the same. When you attempt to open the database in Access 2013 or Access 2016, Access reads the stamp in the following way:

  • If the database version is lower than 16.7, the Large Number data type is not enabled, and you can open the database.

  • If the database version 16.7 or higher, the Large Number data type is enabled, you can only open the database in Access 2016.

Summarizing Large Number data type support for product versions

The following table summarizes the possible situations you may encounter when using the Large Number data type for different product versions. Note that enabling occurs when you add the Large Number data type to a table and save the design or set the option to enable linking and importing.

Tip: For more information on viewing the product version number, see What version of Office am I using?

Status of the Large Number Data Type

Product version: Access 2013 and Access 2016 version number lower than 16.0.7812

Product version: Access 2016 version number 16.0.7812 or higher

Enabled

You cannot open the database and you receive an error message with a help link.

To work around this situation, see "Remove Large Number data type support from a database in Access 2007-2016 file format"

You can open the database.

Local table fields defined with the Large Number data type are treated as large numbers.

You can refresh linked tables. If the columns were previously treated as the Short Text data type, they are automatically converted to the Large Number data type.

Not enabled

You can open the database.

You can refresh linked tables. If columns in the linked table are based on the BigInt data type and were converted to the Short Text data type, they remain so.

The database file version remains the same.

You can open the database.

You can refresh linked tables. If the columns in the linked table are based on the BigInt data type and were converted to the Short Text data type, they remain so.

The database file version remains the same.

Note: The Large Number data type is not supported under any circumstances with the Access file formats (.mdb) prior to the Access 2007-2016 file format.

Determine whether an Access database has the Large Number data type enabled

You may inherit an Access database and want to determine if the Large Number data type is enabled. You can do the following:

Examine the title bar   If the database has been stamped, the title bar says <database name> (Access 2016). Otherwise, the title bar says <database name> (Access 2007-2016).

Examine programmatically View the current database version number. Press CTRL+G to display the Visual Basic Immediate Window, enter ?CurrentDb().Version and then press Enter. If the return value is less than 16.7, support is not enabled. If the return value is 16.7 or higher, then support is enabled.

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Backward Compatibility Considerations

It's important that you understand your database environment if you want to maintain backward compatibility with different file formats. For more information about all Access file formats, see Which Access file format should I use?

Here are three alternatives to consider.

Maintain your current shared database file format environment

To maintain a shared database file format environment with databases in Access 2007-2016 file format (.accdb) and prior file formats (.mdb), do the following:

  • Do not add the Large Number data type as a column to any table.

  • Do not enable the Large Number data type for linking and importing operations. For more information, see Set user options for the current database.

Add Large Number data type support to a database in Access 2007-2016 file format

To add Large Number data type support to a database in Access 2007-2016 file format (.accdb), do the following:

  1. Open the database in Access 2016 (16.0.7812 or higher).

  2. Enable the Large Number data type for linking and importing operations. For more information, see Select settings for how data is displayed and stored in your database.

  3. Refresh the linked tables by using the Linked Table Manager (Select External Data Linked Table Manager, select the relevant tables, and then select OK).

    OR

    Add a field with the Large Number data type to a table and save the table design.

As a result, fields that had the Short Text data type are converted to the Large Number data type.

Remove Large Number data type support from a database in Access 2016 file format

You cannot open a database in Access 2016 file format from versions of Access prior to Access 2016. To work around this issue, do the following:

  1. Create a new database in the 2007-2016 file format and make sure the Large Number data type support for linking and importing operations is not enabled. For more information, see Set user options for the current database.

  2. In the new database, import the objects you want from the original database.

  3. In the new database, link to the tables from the original database.

As a result, fields that had the Large Number data type are converted to the Short Text data type, and the new database is backward compatible with all Access 2007-2016 file formats (.accdb).

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