This tutorial shows you how to use the SQL Server self join to query hierarchical data or compare rows within the same table.

SQL Self Join A self join is a regular join, but the table is joined with itself. Self Join Syntax SELECT column_name (s) FROM table1 T1, table1 T2 WHERE condition;

Nov 21, 2025 · SQL Self Join is used when a table needs to be joined with itself to compare rows within the same table. It helps in finding relationships between records in a single table by …

Jun 13, 2024 · You use a self join when a table references data in itself. E.g., an Employee table may have a SupervisorID column that points to the employee that is the boss of the current …

This tutorial explains the SQL self-join technique and how to apply the self-join to join a table to itself.

The SQL Server SELF JOIN is a regular one where a table (Table1) joins with itself. It uses the unique column within the same table to perform the join. If we have the primary key and …

In SQL Server, the self-join is like a regular join, but it joins a table to itself. Similar to any other join, a self-join requires at least two tables. But instead of adding a different table to the join, …

Aug 4, 2025 · Applies to: SQL Server You can join a table to itself even if the table doesn't have a reflexive relationship in the database. For example, you can use a self-join to find pairs of …

May 12, 2023 · An SQL self join can be used for demonstrating relationships within a single SQL Server table database. Here's how and when to use an SQL self join.

Aug 16, 2024 · Read this SQL Server tutorial to understand how to use the SQL Server SELF JOIN with examples like SQL Server Self Join Recursive and more.

The SQL SELF JOIN is a versatile tool for relating rows within the same table, enabling queries for hierarchies, comparisons, or duplicates. By mastering its syntax, using INNER or LEFT …

Oct 13, 2020 · We discuss the self join and its SQL syntax, with examples to show how the self join can be useful in your everyday work.