Using Multiple Files in FileMaker Solutions
In Chapter 2, "Introducing the FileMaker Architecture," the section "Structuring Solutions and Sub-Solutions" described how you can use multiple files to construct your solution so that files focusing on interface elements are separate from those supporting the data itself. When it comes time to think about deploying your solutions and sub-solutions, you might have to address the issues relating to those files.
The issues center on the fact that you do not have the kind of access to the files and file system on the mobile device that you have on a desktop-based computer. All of your FileMaker files will be together in the FileMaker Go section of the device. Therefore, if you have constructed a complicated file structure (perhaps by connecting files in several folders or even several disks), this structure might not work easily on a mobile device. (In fact, this is very much the issue that you can encounter when deploying files for FileMaker Server. In that case, files are placed in a Databases folder for FileMaker Server, and so complex file/folder relationships are very much as simplified as they are for FileMaker Go.)
The simplest way to organize your files in a multi-file FileMaker solution is to place all the files in a single folder; you can then move that folder around (to the FileMaker Server deployment or to the FileMaker Go deployment) and the files remain together. This means that the links among the files are always within that one folder, with each related file being no more than one step away from any other file.
Before you can use an external file in a multi-file solution, you need to define it to FileMaker. To do so, you use the File, Manage, External Data Sources command, as shown in Figure 4.13.
Figure 4.13 Specify external data sources.
In this dialog, you can name an external data source and specify its location. As the dialog shows in the examples at the bottom, you can use files in other directories and on other servers as external data sources. You can also use non-FileMaker files if they conform to ODBC protocols.
If you are placing a file on a mobile device with FileMaker Go, it is easiest to use the single folder structure described in this section. If you are accessing a FileMaker Server database, you can deploy it as you normally would and simply connect to it from the mobile device.
After you have specified an external data source, you can use it in your relationships graph. Simply click the add table button at the bottom left as shown in Figure 4.14, and you can choose an external data source. (If it is not already set up, you can add it from the dialog, as shown in the figure.) After you have selected the data source, its tables are displayed, and you can select the one you want to use. From then on, everything is the same as if you were using tables within your main database file.