Microsoft Office Tutorials and References

In Depth Information

**Number**

Access Data Types

Single

Positive or negative numbers with up

to 38 zeroes and 7 decimal places

of accuracy. Requires four bytes of

space.

The best choice if you need to store

non-integer numbers or numbers

that are too large to fit in a Long

Integer.

Double

Positive or negative numbers with up

to 308 zeroes and 15 decimal places

of accuracy. Requires eight bytes of

space.

Useful if you need ridiculously big

numbers.

Decimal

Positive or negative numbers with up

to 28 zeroes and 28 decimal places

of accuracy. Requires eight bytes of

space.

Useful for numbers that have lots

of digits to the right of the decimal

point.

Note:
Table 26-2 doesn’t include Replication ID, because you use that option only with the Number data

type (page 723).

Number formatting

The Field Size determines how Access stores your number in the table. However,

you can still choose how it’s
presented
in the datasheet. For example, 50, 50.00, 5E1,

$50.00, and 5000% are all the same number behind the scenes, but people interpret

them in dramatically different ways.

To choose a format, you set the Format field property. Your basic built-in choices

include:

•
General Number.
Displays unadorned numbers, like 43.4534. Any extra zeroes

at the end of a number are chopped off (so 4.10 becomes 4.1).

•
Currency and Euro.
Both options display numbers with two decimal places,

thousands separators (the comma in $1,000.00), and a currency symbol. These

choices are used only with the Currency data type (page 726).

•
Fixed.
Displays numbers with the same number of decimal places, filling in

zeroes if necessary (like 432.11 and 39.00). A long column of numbers lines up

on the decimal point, which makes your tables easier to read.

•
Standard.
Similar to Fixed, except it also uses thousands separators to help you

quickly interpret large numbers like 1,000,000.00.

•
Percent.
Displays numbers as percentages. For example, if you enter 0.5, that

translates to 50%.

•
Scientific.
Displays numbers using scientific notation, which is ideal when you

need to handle numbers that range widely in size (like 0.0003 and 300).

Scientific notation displays the first nonzero digit of a number, followed by a fixed

number of digits, and then indicates what power of ten that number needs to be

multiplied by to generate the specified number. For example, 0.0003 becomes

3.00 × 10
-4
, which displays as 3.00E–4. The number 300, on the other hand,

becomes 3.00 × 10
2
, or 3.00E2.