Database Reference
In-Depth Information
Validation Requirements
When you added validation to the Zip Code field (see
Validation Options
), you asked
FileMaker to accept only numbers and to allow only five digits.
But data type and character count are just two of the eight kinds of validations FileMaker has
up its sleeve. In the Field Options window's Validation tab, you have six more checkboxes.
Most of them work much the same way: They compare what you type against some specific
condition. But one option, “Validated by calculation,” offers a completely flexible way to de-
scribe exactly what you're looking for. Unfortunately, to use it, you need to learn how to per-
form
calculations
(mathematical or logical formulas) with your FileMaker data. They're
covered starting in
Chapter 9
. Until then, here's what the other options do.
Strict Data Type
This option lets you pick one of three specific validations. You've already seen “Numeric
only,” which insists that every character in your field be a number. “4-digit Year Date” tells
FileMaker to expect a date value, and that the year has to be four digits long (2014 instead of
14). This choice works with text, date, and timestamp fields.
“Time of day” tells FileMaker that only time values that represent real clock times are ac-
ceptable. Since time fields can hold any number of hours, minutes, and seconds, you can
enter something like
237:34:11
to mean “237 hours, 34 minutes, 11 seconds.” But if the field
is
supposed
to be the time of your lunch meeting, that value doesn't make sense. This option
prevents its entry. It applies to text and time fields (timestamp fields
always
require a time of
day).
NOTE
The “4-Digit Year Date” and “Time of Day” options also work on Number fields.
Not Empty
If you insist on having
something
in a field, select the “Not empty” validation option. This
option makes FileMaker complain if you try to commit the record without entering
something
.
Unique
The “Unique value” option prevents you from putting the same value in a field for two dif-
ferent records. It comes in handy for things like product codes, account names, and course
numbers.
