MultiValue database deals with three dimensional data modelling where they focus mainly on three-dimensional data structures like Fields, Values, and Subvalues.
A field, or column, is the same as it would be in a normalized database.
A Value is a further breakdown of a column. For example, in a normalized database there might be columns defined for Address1, Address2, Address3. In a MultiValue database there would be a definition for a column named Address, and stored in that column would be either one, two, three, or more values. These different values would be delimited by a special character known as a Value Mark.
A Subvalue is a further breakdown of a value. For example, if there is a column defined for Phone, and there is a value called Home, there may be two sub values for the home phone number- perhaps the main number and a home office phone number.
Another distinct advantage to the MultiValue world is that the tables are extremely flexible. Columns can usually just be added to the database definition and used immediately. There is no need to shut down the database , lock out the users, add the column, and rebuild the database. A new column is simply added to a dictionary and that column is then immediately available.
Examples : jBASE etc.
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