Nov 01 Databases2
Volume Number: 17 (2001)
Issue Number: 11
Column Tag: Databases
by Mark Shuchat-Marx
All in the Family: Relational Databases in FileMaker Pro 5
Apple's FileMaker Pro database has long been the standard to beat for the Mac world, much as Microsoft Access is the database standard for Windows. While many users keep records in FileMaker of video collections or recipes, it does have some considerably more advanced features, such as ODBC (stands for Open Database Connectivity, a standard cross-platform protocol for accessing data from SQL servers) and use of relationships. It is this second feature that we will examine here.
Relationships in databases have nothing to do with giving flowers or making a commitment. It has everything to do with how different database files share data with each other. Suppose that you are constructing an expense report database and you don't want to type in the employee's name, department number, and so on every time you create a new record. If you already have an existing employee database, you can set up a relationship between the two files that will keep the data organized for you. (For this example, we took the sample files "Personnel Records" and "Expense Report" included as part of the FileMaker installation.)
In the expense report file, go to the "Define Relationships" item in the File menu and create a relationship between the expense report and the personnel files, linking the related fields in the two databases. In this example, we linked the Employee ID fields from the two database files so that data in the expense report will be automatically filled in based on data in the personnel file. Why did we choose the Employee ID field? Because in this example that is the one field guaranteed to be unique for each and every person.
The second step is to set up the fields you want to be automatically filled in. In our example, we want FileMaker to automatically fill in the employee's first and last names whenever we enter in the Employee ID number. Go to "Define Fields" in the File menu and scroll down to the First Name and Last Name fields, then select First Name and press the Options button. Check off "Lookup" under the "Auto-Enter" tab, then press the Specify button.
Now select the relationship you created earlier, and you will see the fields from the personnel file. Select the "First Name" field, make sure the "Don't copy contents if empty" box is checked off, then press OK. Do the same for the Last Name field.
You are now ready to create records. Put a few sample records into the Personnel Records file, making sure each person has a unique Employee ID number. Now switch to the Expense Report file and create a new record, Put in an Employee ID number of the person for whom you want to fill out an expense report. And voilà, you will see that the person's first and last names are automatically entered into the form.
Another way to do this is simply to put a field from the related form onto the original. In our example, we put the First Name, Last Name and Title fields from Personnel Records (using the relationship created earlier) onto the Expense Report form directly. To do this, put the form into Layout mode, and then drag the "Field" item from the toolbar on the left side of the window to the desired location on the form. Select the desired field from the list that appears.
Once you select the field and it's placed on the form, you can manipulate it like any other field, changing the size, font, color, and so on. On your form, it looks like any other field from the original file, except that in layout mode, the field name begins with two colons (::)
Now go back into Browse mode and create a new record. Put in an existing Employee ID number from Personnel Records and you will see the fields you just placed populated with data from Personnel Records.
A third method of using a database relationship is to use a portal. This is a way of placing several instances of a field on a form. Suppose you want to create a travel record form to track travel records that groups take. Create a relationship between the travel file and the aforementioned Personnel Records file, then place a portal on the layout form. Once you are back in Browse mode, you can then use the portal to display multiple records from Personnel Records in a single travel record.
In a way, you can use the portal even in database files that are not related. In such files, this is called a repeating field, and is a way of containing a relational database within a single file. Suppose you're creating a database to keep track of your video collection and you want to put in a field to hold cast members. You can create a single text field and use commas to separate the stars' names (e.g., "Humphrey Bogart, Ingrid Bergman, Claude Rains" and so on) or you can designate the field as a repeating field.
To do this, go into the "Define Fields" item in the File menu, select the field you want to repeat and press the Options button. Under the "Storage" tab, you'll see an option to turn on repeating fields, as well as the number of times you want the field repeated. Once you press OK, you'll see "Repeating" listed next to the field name under Options. [display "repeating field list" picture here]
Now, when you place the field on your form, it will look like any other field. But if you select the field and select "Field Format" from the Format menu (or control-click on the field and select "Field Format" from the contextual menu), you'll see an option to display anywhere from none to all of the field's repeats. You can also place the repetitions horizontally or vertically. This will let you enter data on multiple cast members within one field.
The ability to use relationships in linking databases together is one of FileMaker Pro's strongest features. With several ways to do it, you are sure to find a method that fits your requirements.
As of this writing, FileMaker Pro 5.5 has been introduced, and has replaced version 5 on the store shelf. The biggest change in 5.5 is that the program now comes in two versions: a Classic version for OS 8.1 or higher, and a Cocoa version for OS X. The Classic version requires a Power Mac with 32MB of RAM and running Mac OS 8.1-9.1. The Cocoa version requires an OS X-capable Power Mac G3 or G4 (upgrade cards are not supported) with 128MB of RAM and running Mac OS X.
The list price for a new copy of 5.5 is $249, with a price of $149 for registered owners of FileMaker 2.1 or later. More information, including downloadable demo copies of both Classic and Cocoa versions, is available at http://www.filemaker.com.
Mark Shuchat-Marx is a longtime Mac technician, consultant, and writer. He lives in the foothills of Albuquerque with his wife Jacqueline, their cats Gingie and Pyewacket, and a Power Mac G4 named Godzilla. You can reach him at firstname.lastname@example.org.