Data types listed here apply only for personal GDBs
| Name |
Specific range, length, or format |
Size (Bytes)
|
Applications |
| Short integer |
-32,768 to 32,767 |
2 |
Numeric values without fractional values within specific range; coded values |
| Long integer |
-2,147,483,648 to 2,147,483,647 |
4 |
Numeric values without fractional values within specific range |
Single precision floating point number (Float)
|
Approximately
-3.4E38 to 1.2E38 |
4 |
Numeric values with fractional values within specific range |
| Double precision floating point number (Double) |
Approximately
-2.2E308 to 1.8E308
|
8 |
Numeric values with fractional values within specific range |
| Text |
Up to 64,000 characters |
Varies |
Names or other textual qualities |
| Date |
mm/dd/yyyy
hh:mm:ss
A/PM |
8 |
Date and/or time |
Choosing a data type
Numeric
In choosing a numeric data type, first consider the need for whole numbers versus fractional numbers. For whole numbers, specify a short or long integer. For numbers with decimal places, specify a float or a double.
Secondly, when choosing between a short or long integer, or between a float and double, choose the data type that takes up the least storage space required. This will not only minimize the amount of storage required but will also improve performance. If you need to store integers between -32,768 and 32,767 only, specify the short integer data type, because it takes up only 2 bytes, whereas the long integer data type takes up 4. If you need to store fractional numbers between -3.4E-38 and 1.2E38 only, specify the float data type, because it takes up 4 bytes, whereas the double data type takes up 8.
Text
A text field represents a series of alphanumeric symbols. A numeric value i.e. 123 can be entered but as text it is no longer quantitative and cannot be used in mathematical calculations.
Date
When a date field is assigned to an attribute in the table for a feature class this is passed along to ArcPad for the data entry form in the form of a calendar. To accept the current data put a check in the box beside the date. To change the date tap on the date field and you will see the calendar.
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