What is Multivalued Attribute in DBMS?
FREE
As the name implies, multivalued attributes in DBMS contain more than one value at a time for an entity instance from a set of possible values, which is the opposite of how single-valued attributes function. Limit constraints, either upper or lower limits, may be applied to multi-valued attributes.
Curly braces {} can be used to indicate multivalued attributes inside the co-centric elliptical shape that represents these attributes.
Example:
- Phone number of a student: Landline and mobile.
- Email ID of a student: Personal email ID and college email ID.
Transform Your Career
Choose from our industry-leading programs designed for career success
Modern Software and AI Engineering Program
Master full-stack development with AI integration
+1000 moreModern Data Science and ML with specialisation in AI
Advanced data science techniques with AI specialization
+1000 moreAdvanced AIML with Specialisation in Agentic AI
Deep dive into AIML with focus on Agentic systems
+1000 moreDevOps, Cloud & AI Platform Engineering
Build and manage AI-powered cloud infrastructure
+1000 moreAI Engineering Advanced Certification by IIT-Roorkee
Premier AI engineering certification from IIT-Roorkee
What are the Problems Associated with Multivalued Attributes?
Multivalued attributes can impair the meaning of the data in the database, significantly slow down searching, and put needless limitations on the amount of data that can be recorded.
What are the Examples of Multivalued Attributes in DBMS?
There can be multiple examples of the multivalued attributes in DBMS. For example, phone number, email ID, nominee name on some insurance, dependent name, etc. we would be understanding some of the examples on details.
Example - 1: ER Model of Student A student can have multiple phone numbers. In this case, the phone number can be classified as a multivalued attribute of the student entity and these multi-valued attributes can be marked inside the co-centric elliptical shape.
| Attribute Name | Attribute Type |
|---|---|
| Student_Name | Single Value |
| Roll_No | Single Value |
| Phone_Number | Multi-Valued |
| Email_ID | Multi-Valued |
Based on the above illustration, the Student entity has the following four attributes: As previously mentioned, the attributes Student_Name and Role_No are single-valued; however, the attributes Phone_No and Email_ID, which are represented by co-centric ellipses, are multi-valued. We require these attributes to be multi-valued so they may contain several values at once for an entity instance because each student in the real world can submit more than one email address and a phone number.
Learn More:
Scaler Placement Report and Statistics
Scaler learners achieved 2.5x salary growth with average post-Scaler CTC reaching ₹23L.
Conclusion
- Multivalued attribute in DBMS is the reverse of the single-valued attributes.
- A relation does not allow multivalued attributes. There can only be one value at the intersection of a column and a row.
- Multivalued attributes in DBMS are used when we need to store one or more values for an attribute.
- The name of the attribute is contained inside a double oval shape that is used to symbolize a multivalued attribute.
- A multivalued attribute in DBMS needs to be resolved into a single-valued attribute.
Google
Amazon
Microsoft
Flipkart
Adobe1200+ more