Structuring Database for Accounting

the table as such is called a relation . The data type describing the types of values ( such as text value, numeric values, date values, currency value, etc. ) that can appear in each column is called a domain. A domain is a set of indivisible values.

Associated with every domain is a data type such as Number, Text, Currency, Date/Time, etc. Each domain must also be named so as to help in interpreting its values. Besides this, a domain must be given a format and any additional information to enable correct interpretation of values. For example, a numeric domain such as distance should have units of measurement: Miles or Kilometers (a) Relations : A relation schema is made up of a relation name and a list of its attributes.

Each attribute is the name of role played by some domain in the relation schema . A relation is given an identity by its name and description by its schema. The degree of a relation is indicated by the number of attributes it contains. For example, the degree of a relation schema