| Author: Manigandan 29 Jun 2009 | Member Level: Gold Points : 2 |
Hi,
Nice one keep posting more...
We can also use Union in a join Query like this,
SELECT employees.Lastname, employees.Firstname, invoices.Sale, invoices.Price
FROM employees
INNER JOIN invoices
ON employees.id = invoices.EmployeeID
UNION
SELECT employees2.Lastname, employees2.Firstname, invoices.Sale, invoices.Price
FROM employees2
INNER JOIN invoices
ON employees2.id = invoices.EmployeeID;
Thanks,
Mani
|
| Author: Viji RAJKUMAR 29 Jun 2009 | Member Level: Diamond Points : 2 |
hi Manig,
Thanks For your response.
In this article I took a very simple example to explain the difference between UNION and UNION ALL.
Event if we want to include specific where clause or ORDER by clause we can add it.
SELECT EmployeeID, lastName
FROM [dbo].[Employees] ORDER BY EmpID
UNION
SELECT EmployeeID, Address
FROM [dbo].[Employees1] WHERE EMPID NOT IN (1001,2001)
Note:
UNION ALL works faster than UNION as it does not perform select distinct.
If you know that you should combin all recordset use UNION ALL
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