datafeltet

A datafeltet, or data field, is the smallest unit of data in a record or data structure. It represents a named element that holds a single value of a specified data type. In relational databases, a field corresponds to a column in a table, and each row contains a value for that column. Fields have properties such as name, data type (for example integer, decimal, string, date/time, boolean), length or precision, and constraints like nullable, default value, unique, or primary/foreign key.

Fields are defined within data models and schemas, often described in data dictionaries to support governance and understanding of the data. Validations enforce data quality, including range checks, format patterns (such as email addresses), and referential integrity through foreign keys. In practice, fields are the targets of data capture, data transformation, and data validation in both storage systems and data pipelines.

In forms and user interfaces, datafeltet corresponds to input controls and often includes client-side validation in addition to server-side checks. In data exchange formats, fields appear as columns, properties, or elements in records, with established naming and encoding conventions. Common challenges include inconsistent naming, missing values, and type mismatches, as well as changes to the schema over time that require backward-compatible evolution.

Example: a customer table might define fields such as customer_id (integer, primary key), name (string), email (string, unique), date_of_birth (date), and is_active (boolean).