VISUAL QUICKPRO GUIDE FileMaker Pro 7 Advanced FOR WINDOWS AND MACINTOSH [Electronic resources] نسخه متنی

Repeating vs. Related Fields

Many FileMaker users are excited when they discover the FileMaker repeating field. It seems to save time while you're defining fieldsa boring stage for many in creating a table. A repeating field allows you to have multiple entries in one field, but have them appear on a layout as if they were separate entries. One practical use for a repeating field might be for people with more than one email address. Repeating fields allow you to avoid the tedium of making several fields labeled "email 1," "email 2," and so on.

On the other hand, most accomplished FileMaker developers use repeating fields sparingly or not at all, because you can attain many of the same results more easily by using related fields. Repeating fields have significant disadvantages. Usually, they are treated as one indivisible unit. You can only sort repeating fields by their first entry, and you can't create subtotals for particular entries. Although there is a calculation formula to pry out a particular repetition from the rest (GetRepetition), in general, individual items in repeating fields are very difficult to extract for a report.

For all of these reasons, whenever you're considering using a repeating field, ask yourself whether a related table makes more sense. (It usually does.)

Tip

Phone numbers are a frequent use for a repeating field because youcan enter all of the numbers for a particular person in one place. On the other hand, instead of creating a repeating field, you could create a text match field as both a relationship and a label for each phone number (Figure 6.25).