Multivalued attributes in database design are typically addressed by creating separate tables or utilizing complex data types.

In the realm of database design, multivalued attributes are those that can hold more than one value for a single entity. For example, an individual may have multiple phone numbers or email addresses. These attributes present a challenge in database design because they violate the principles of the First Normal Form (1NF), which requires that each attribute in a table must contain atomic (indivisible) values.

One common method for managing multivalued attributes is to establish separate tables. For instance, if we have a ‘Person’ table that includes a multivalued attribute called ‘Phone Numbers’, we can create a distinct ‘Phone Numbers’ table. This new table would consist of two columns: ‘Person ID’ and ‘Phone Number’. Each entry in this table would represent a single phone number associated with a person, where ‘Person ID’ serves as a foreign key linking back to the ‘Person’ table. This approach allows us to store multiple phone numbers for each individual while ensuring that the data complies with the First Normal Form.

Another strategy involves the use of complex data types, such as arrays or JSON objects, to encapsulate multiple values within a single attribute. This method is supported by some modern database management systems (DBMSs), such as PostgreSQL. However, employing complex data types can complicate data querying and manipulation, often making it less efficient compared to the separate table approach.

In certain scenarios, one might consider concatenating the values into a single string, separated by a delimiter. While this method may seem straightforward, it is generally discouraged as it complicates querying and data manipulation, increasing the risk of data anomalies.

In summary, addressing multivalued attributes in database design necessitates careful consideration. The chosen method must align with the specific requirements of the database and the capabilities of the selected DBMS.