Access™ 2007 VBA Programmer's Reference

3.7. Access Data Engine

Access 2007 ships with a custom version called the Access data engine (also known as ACE). In addition to being totally compatible with the Microsoft Jet 2000 and 2002-2003 file formats, the Access data engine introduces the new ACCDB file format, which provides a richer environment and greater reach. "Rich" refers to powerful new features such as multi-value fields (MVF) and attachment field types. The term "reach" refers to more than being specifically designed to integrate with SharePoint. Although that is a huge part of it, reach also refers to better integration with Excel, SQL Server, Outlook, and a multitude of other programs. The Access data engine can use Open Database Connectivity (ODBC) or installable indexed sequential access method (ISAM) drivers to link tables to external data sources.

One of the key features of the ACCDB format is the capability to store multi-valued lookup fields (also referred to as complex data). Storing multi-valued fields requires the presence of a new system table, MSysComplexColumns, plus a series of built-in schema tables. The MSysComplexColumns table and the built-in schema tables are automatically created whenever a new ACCDB file is created.

3.7.1. Multi-Value Fields

Most database programs, including earlier versions of Access, allow you to store only a single value in each field. In Office Access 2007, however, you can now create a lookup field that enables you to store more than one value. In effect, it creates ...