How to create an instance in SQL Server 2008

Question

I have SQL Server 2005 Express installed. Later I upgraded to SQL Server 2008. I don't know much about instances, but when I log in to SQL Server 2005 and I log in to SQL Server 2008, it shows the same number of databases. In addition, when I create a database in SQL Server 2008, it is displayed in SQL Server 2005.

Any idea how I can create a separate instance of SQL Server 2008?

If possible, explain step by step.

thanks

Answer 1

A SQL Server database instance is simply a named installation of SQL Server. The first that you install on any given machine is usually the default instance, which does not have a specific name - you simply connect to it using the name (local) or the name of the server machine.

SQL Server Express is usually installed as an SQLExpress instance, so the instance is called SQLExpress, and you connect to it using (local)\SQLExpress or .\SQLExpress or MyServerMachine\SQLExpress .

SQL Server instances are completely independent of each other, and you can basically install as many as you want - you just need to use unique instance names for each. But when you start the SQL Server installation again, it will show you which instances are already installed and offer you a new instance name for the new installation. There was no harm.

Answer 2

Run the installer again, and when asked if you want to use the default or named instance, specify the named instance with a different name. The default instance looks like this:

 servername 

A named instance is as follows:

 servername\instancename 

Answer 3

"you can install as many as you want"

In 2008, there are restrictions, for example 50.

http://technet.microsoft.com/en-us/library/aa174516 (v = sql.80) .aspx Microsoft does not support more than 16 instances on a single computer or failover cluster.

There are a few more limitations.