A self-referencing relationship is when a table has a relationship with itself. So instead of linking to a different table, a record in the table links to another record in that same table.
Real example:
Take the Employee table. You’d add a lookup column called something like “Manager” on the Employee table, and that lookup points back to the Employee table itself — because a manager is also an employee.
So one row, such as James Thomas, can have another row, Sophia Davis, set as their Manager. Sophia is also just another record in the same Employee table.
Simple way to remember it:
Normal lookup → points to a different table
Self-referencing lookup → points back to the same table
Why it’s useful:
It lets you build hierarchies without creating extra tables. You don’t need a separate “Manager” table — you just reuse the same Employee table and link records to each other.
