4. Table Structure in DBMS

A table is a two-dimensional structure in a database that stores data in the form of rows (tuples) and columns (attributes).

  • Each row represents one record.
  • Each column represents a specific data field.

2. Components of a Table

  • Table Name → Unique name to identify the table (e.g., Students).
  • Attributes (Columns) → Data fields (e.g., StudentID, Name, Age).
  • Tuples (Rows) → Actual data entries (e.g., one student’s record).
  • Degree → Number of attributes (columns).
  • Cardinality → Number of tuples (rows).
  • Domain → Allowed values for each attribute (e.g., Age must be an integer).
  • Constraints → Rules to maintain data consistency (Primary Key, Foreign Key, Not Null, Unique, Check).

  3. Key Points (Quick Recap)

  • Table = Rows + Columns
  • Row = Record (tuple)
  • Column = Attribute (field)
  • Degree = Number of columns
  • Cardinality = Number of rows
  • Constraints = Rules that ensure correctness and uniqueness of data