How can I determine installed SQL Server instances and their versions?

Question

At a command line:

SQLCMD -L

or

OSQL -L

(Note: must be a capital L)

This will list all the sql servers installed on your network. There are configuration options you can set to prevent a SQL Server from showing in the list. To do this...

At command line:

svrnetcn

In the enabled protocols list, select 'TCP/IP', then click properties. There is a check box for 'Hide server'.

You could query this registry value to get the SQL version directly:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\90\Tools\ClientSetup\CurrentVersion

Alternatively you can query your instance name and then use sqlcmd with your instance name that you would like:

To see your instance name:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\Instance Names

Then execute this:

SELECT SERVERPROPERTY('productversion'), SERVERPROPERTY ('productlevel'), SERVERPROPERTY ('edition')

If you are using C++ you can use this code to get the registry information.

All of the instances installed should show up in the Services Snap-In in the Microsoft Management Console. To get the instance names, go to Start | Run | type Services.msc and look for all entries with "Sql Server (Instance Name)".

-- T-SQL Query to find list of Instances Installed on a machine

DECLARE @GetInstances TABLE
( Value nvarchar(100),
 InstanceNames nvarchar(100),
 Data nvarchar(100))

Insert into @GetInstances
EXECUTE xp_regread
  @rootkey = 'HKEY_LOCAL_MACHINE',
  @key = 'SOFTWARE\Microsoft\Microsoft SQL Server',
  @value_name = 'InstalledInstances'

Select InstanceNames from @GetInstances 

I know this thread is a bit old, but I came across this thread before I found the answer I was looking for and thought I'd share. If you are using SQLExpress (or localdb) there is a simpler way to find your instance names. At a command line type:

> sqllocaldb i

This will list the instance names you have installed locally. So your full server name should include (localdb)\ in front of the instance name to connect. Also, sqllocaldb allows you to create new instances or delete them as well as configure them. See: SqlLocalDB Utility.

If you just want to see what's installed on the machine you're currently logged in to, I think the most straightforward manual process is to just open the SQL Server Configuration Manager (from the Start menu), which displays all the SQL Services (and only SQL services) on that hardware (running or not). This assumes SQL Server 2005, or greater; dotnetengineer's recommendation to use the Services Management Console will show you all services, and should always be available (if you're running earlier versions of SQL Server, for example).

If you're looking for a broader discovery process, however, you might consider third party tools such as SQLRecon and SQLPing, which will scan your network and build a report of all SQL Service instances found on any server to which they have access. It's been a while since I've used tools like this, but I was surprised at what they found (namely, a handful of instances that I didn't know existed). YMMV. You might Google for details, but I believe this page has the relevant downloads: http://www.sqlsecurity.com/Tools/FreeTools/tabid/65/Default.aspx