•    The structure file (denoted by the file extension .4DB) contains all of your specifications for the design of the database.

•  The structure resource file (denoted by the file extension .RSR) contains resources used by the structure file. These resources might include pictures or strings.

•  The data file (denoted by the file extension .4DD) contains your data and any indexes you build.

•  The data resource file (denoted by the file extension .4DR) contains resources used by the data file.

 

On Macintosh, a 4th Dimension database consists of two desktop files, the structure file and the data file. The structure resource file is merged with the Macintosh structure file and the data resource file is merged with the Macintosh data file.

The structure file has no suffix on Macintosh, while the data file has the suffix .data.

Naming Directories

If you check the Create Database Folder check box in the Welcome dialog box, the directory (folder on Macintosh) is given the name you assign to the database.

For example, if you name a database Contacts, the directory will be named Contacts, the structure file will be named Contacts.4DB, the structure resource file will be named Contacts.RSR, the data file will be named Contacts.4DD, and the data resource file will be named Contacts.4DR.

On Macintosh, the folder is given the name you assigned to the database, followed by an “ƒ”. The data file is also given the same name, followed by “.data”.

For example, if you name a database “Contacts,” the folder will be named Contacts ƒ, the structure file will be named Contacts, and the data file will be named Contacts.data.

On Windows, the data resource file (denoted by the file extension .4DR) contains Macintosh resources pertaining only to the data file, such as the WEDD resource that links a data file with a particular structure file.

Structure and Data File Locations

4th Dimension does not require that the structure and data files have the same names, be in the same directory, or be on the same volume.

You can move either the structure or data file to new locations on the same hard disk or to different hard disks. However, the structure and resource files must always be in the same location.

In the same way, the data resource file must be kept in the same location as the data file.

When you open a structure file, you can choose to use a data file other than the one you initially created or you can create a new data file.

This option gives you the ability to use more than one set of data with the same structure file. For example, a developer can use a “dummy” data file while working on the database off-line and then redeploy the improved structure file with the “real” data file when the development is finished.

If you separate the data file from the structure file by moving it, you will need to indicate the data file’s new location. By displaying the Open Data File dialog box, 4th Dimension asks for the location of the
data file the first time you open the structure file.