Microsoft Access 2010 Bible

Part III: More-Advanced Access Techniques

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database file. Assume for a moment that the entire database is contained within a single .accdb

on the file server, and the database has been enabled for shared data access. Each workstation in

Figure 21.2 has a full copy of Access (or the Access runtime) installed.

FIGURE 21.2

A database kept on a file server can generate a large amount of traffic on the network.

Workstation A

Entire

Access

database

File server

Network cable

Workstation B Workstation C

Now, what happens when the user on Workstation C opens the database? The Access installation

on that machine must locate the .accdb on the file server, open that file, and start up the applica-

tion. This means that any splash forms, queries, and other startup activities must take place across

the network before the user is able to work with the database. Any time a form is opened or a

query is run, the information necessary to fulfill the query must travel across the network, slowing

the operation. (In Figure 21.2, the network load is indicated by a thick dashed line.)

The situation shown in Figure 21.2 is made even worse when more than one user is using the

same database. In this case, the network traffic is increased by the queries, opening of forms, and

other operations performed by each additional user’s copy of Access. Imagine the dashed line get-

ting thicker with each operation across the network.

The split-database model is illustrated in Figure 21.3. Notice that the back-end database resides on

the server while individual copies of the front-end database are placed on each workstation. Each

front-end database contains links to the tables stored in the back-end .accdb file. For perfor-

mance reasons, the front-end databases may also contain certain tables that are more efficiently

used from the local machine than when they’re stored on the file server. The front-end databases

also contain the forms, reports, queries, and other user-interface components of the application.