Properties of a Table
Explore the fundamental properties that define a relational database table such as unique rows ensured by primary keys, atomic column values, uniform data types, and how the order of rows and columns is irrelevant. This lesson helps you grasp how these properties support data integrity and flexibility in database design.
Properties of relational tables
Although we defined relations as a table of values, certain characteristics make a relation different from a table. We highlight these properties with the help of the following table:
Student Relation
| Stud_Id | First_Name | Last_Name | Class | Major |
|---|---|---|---|---|
| 1 | Adam | Smith | Junior | CS |
| 2 | Jonathan | Joestar | Sophomore | Economics |
| 3 | Lucas | Klein | Senior | Physics |
| 4 | Brandon | Jones | Freshman | Biology |
| 5 | Ian | Damiani | Junior | Sociology |
1. Each row is unique
This property ensures that no two rows in a relational table are identical; there is at least one column, or set of columns, whose values uniquely identify each row in the table. Such ...