|
|
In a relational database, an item of information, such as a chromosome number, or the centimorgan length on a genetic map. Some fields are numeric, while others are textual; some are long, while others are short. In addition, every field has a name, called the field name. In database management systems, a field can be required, optional, or calculated. A required field is one in which you must enter data, while an optional field is one you may leave blank. A calculated field is one whose value is derived from some formula involving other fields. You do not enter data into a calculated field; the system automatically determines the correct value. A collection of fields is called a record. See also parameter.
|
|