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SQL RIGHT JOIN

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The SQL Right Join is a Join used to return all the records (or rows) present in the Right table and matching rows from the Left table.

NOTE: All the Unmatched rows from the Left table will filled with NULL Values.

SQL RIGHT JOIN Syntax

The basic syntax of the Right Join in SQL Server is as follows:

-- SQL Server RIGHT JOIN
SELECT Table1.Column(s), Table2.Column(s),
FROM Table1
 RIGHT OUTER JOIN
     Table2 ON
   Table1.Common_Column = Table2.Common_Column

--OR We can Simply Write it as
SELECT Table1. Column(s), Table2. Column(s),
FROM Table1
 RIGHT JOIN
     Table2 ON
   Table1.Common_Column = Table2.Common_Column

TIP: The SQL Server Right Outer join can also be called as Right Join so it is optional to use the Outer Keyword.

Let us see the visual representation of the Sql Server Right Outer join for better understanding.

SQL RIGHT OUTER JOIN

From the above image, you can understand easily that, SQL Right Outer join displays all the records present in Table 2 and matching records from Table 1

In this article, we will show you, How to write Right Join in SQL Server. For this, We are going to use two tables (Employee and Department) present in our [SQL Server Tutorials] Database.

Data present in the Employee Table is:

SQL RIGHT JOIN

Data present in the Department Table is:

SQL RIGHT JOIN 0

SQL Right Join Select All Columns

The following SQL Right Join Query will display all the columns present in the Department table, and matching records from the Employees table

-- SQL Server RIGHT JOIN Example
SELECT *
FROM [Employee]
 RIGHT OUTER JOIN
     [Department] ON
 [Employee].[DepartID] = [Department].[id]

OUTPUT

SQL RIGHT JOIN 1

SQL Right Join – Avoid Outer keyword

As we said before, it is optional to use an Outer keyword. Let me remove the Outer keyword, and work will RIGHT JOIN

-- SQL Server RIGHT JOIN Example
SELECT *
FROM [Employee]
 RIGHT OUTER JOIN
     [Department] ON
 [Employee].[DepartID] = [Department].[id]

OUTPUT

SQL RIGHT JOIN Example 1

If you observe the above screenshot, Although we have 15 records in Employee table, Sql Server Right join is displaying 13 records. This is because,

  • Department Id for 14th and 15th records in Employee table are NULLS so there are no matching records in the right table.
  • If you observe the 8th and 9th records, they are displaying NULL values. Because in the Employee table there are no matching records for Department Id 3, 4 (Module Lead and Team Lead) in the Department table. So they are simply replaced by NULLS.

NOTE: The [Department ID] column is repeated twice, which is annoying to the user. By selecting individual column names we can avoid unwanted columns so, Please avoid SELECT * Statements in Right Join in Sql Server

SQL Right Join Select Few Columns

Please place the required columns after the SQL SELECT Statement to avoid unwanted columns

-- SQL Server RIGHT JOIN Example
SELECT [FirstName]
      ,[LastName]
      ,[DepartmentName]
FROM [Employee]
  RIGHT JOIN
     [Department] ON
  [Employee].[DepartID] = [Department].[id]

OUTPUT

SQL RIGHT JOIN 2

Above query will perfectly work as long as the column names from both tables (Employee and Department) are different like above. What happens if we have the same Column names in both the tables? Well, you will end up in a mess. Let us see how to resolve the issue.

Before we get into the solution, let me show you one practical example. As you can see, we are using the above Sql Server right outer join query but we added id from department table as an additional column.

-- SQL Server RIGHT JOIN Example
SELECT [FirstName]
      ,[LastName]
      ,id
      ,[DepartmentName]
FROM [Employee]
RIGHT OUTER JOIN
     [Department] ON
           [Employee].[DepartID] = [Department].[id]

You can see from the below screenshot, it is throwing an error : Ambiguous column name id. This is because, id column is present in both Employee, and department table. And SQL Server don’t know which column you are asking it to retrieve.

SQL RIGHT JOIN Example 2

To resolve this kind of issues you always have to use table name before the column name. The following Sql Server right outer join query is using ALIAS table name before the column names.

By this approach, we can inform the SQL Server, that we are looking for id column belonging to the department table.

We can simply write the above query as:

-- SQL Server RIGHT JOIN Example
SELECT Emp.[FirstName] AS [First Name]
      ,Emp.[LastName] AS [Last Name]
	  ,Dept.id 
      ,Dept.[DepartmentName] AS [Department Name]
FROM [Employee] AS Emp
RIGHT JOIN
     [Department] AS Dept ON
          Emp.[DepartID] = Dept.[id]

OUTPUT

SQL RIGHT JOIN Example 3

SQL Right Join Where Clause

The SQL Server right outer join also allows us to use Where Clause to restrict the number of rows returned by the right Join. In this example, we will use that WHERE Clause along with the Right Outer Join.

-- SQL Server RIGHT JOIN Example
SELECT Emp.[FirstName] AS [First Name]
      ,Emp.[LastName] AS [Last Name]
      ,Dept.[DepartmentName] AS [Department Name]
FROM [Employee] AS Emp
RIGHT JOIN
     [Department] AS Dept ON
          Emp.[DepartID] = Dept.[id]
WHERE Emp.[FirstName] IS NOT NULL

OUTPUT

SQL RIGHT JOIN Example 4

SQL Right Join Order By Clause

The SQL Server Right Join allows us to use Order By Clause in Right Join to rearrange the order of the records.

-- SQL Server RIGHT JOIN Example
SELECT Emp.[FirstName] AS [First Name]
      ,Emp.[LastName] AS [Last Name]
      ,Dept.[DepartmentName] AS [Department Name]
FROM [Employee] AS Emp
 RIGHT JOIN
     [Department] AS Dept ON
    Emp.[DepartID] = Dept.[id]
ORDER BY [FirstName] ASC

OUTPUT

SQL RIGHT JOIN 3

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