Database Reference
In-Depth Information
which that field isn't empty. If it's empty, then it simply doesn't contribute to the count.
Choose a field that's
never
empty if you want to be sure you count
every
record. You can use
this property to your advantage, though. If you want your count to reflect just the flagged re-
cords, then count the Flag field instead. In
Figure 15-3
, the Orders column uses this option.
This option gives you a “Running count” checkbox. It works like running total but has an op-
tion that running total doesn't offer. When you turn on “Running count,” the “Restart sum-
mary for each sorted group” checkbox becomes available. This option lets you produce a
column like Running Count in
Figure 15-3
. This column counts up with each state, keeping a
running count. But it's set to restart numbering based on the Region field. Notice that the
running count starts over with each new region.
Minimum and Maximum
If you want to know the
smallest
or the
largest
value in a group, use Minimum or Maximum.
Both are very simple: Just pick the field you want to evaluate. No checkboxes, no extra lists.
Number, date, time, and timestamp field types are available for minimum and maximum
summarization, as are calculation fields with number, date, time, and timestamp results. You
can use these to see the largest number of orders in your database, or the date of the earliest
sale.
Standard Deviation of
If you're into statistics or just devious, use
Standard Deviation of
.
It gives you a field that
calculates its namesake for the selected number field. It also has a “by population” checkbox,
which is a little oddly named (it probably should be called “of population”). Turn this check-
box on if your records represent the entire population in your particular domain, and
FileMaker uses the formula for the standard deviation of a population. Turn it off to calculate
the standard deviation of a
sample
.
NOTE
If none of this makes sense to you, then rest assured you don't need to understand standard deviation
to use summary fields. But if you're cursed with a curious mind, Google
define:standard deviation
and go to town.
Fraction of Total of
“Fraction of Total of” is the most complex summary option. It looks at the total for the
group
you're summarizing, as well as the total for the entire database. It then reports what portion
of the overall total the group represents, as a decimal number. If all your sales were in Cali-
