72
votes

I installed LocalDb using the SqlLocalDb.msi package and I can connect to it using SSMS using the server name (LocalDb)\v11.0. So far so good. The problem is that when I try to connect to it via a .NET 4.5 application I get the error

The server was not found or was not accessible.

I started with the connection string Data Source=(LocalDb)\v11.0 and then added many things to no avail (integrated security true/sspi, attaching a db, using instances, etc.)

10
Looking at all these answers, I thought LocalDb was supposed to make things simpler? Seems to be another layer of complexity and confusion.Steve Smith

10 Answers

39
votes

I think you hit the same issue as discussed in this post. You forgot to escape your \ character.

83
votes

I am totally unable to connect to localdb with any tool including MSSMA, sqlcmd, etc. You would think Microsoft would document this, but I find nothing on MSDN. I have v12 and tried (localdb)\v12.0 and that didn't work. Issuing the command sqllocaldb i MSSQLLocalDB shows that the local instance is running, but there is no way to connect to it.

c:\> sqllocaldb i MSSQLLocalDB
Name:               MSSQLLocalDB
Version:            12.0.2000.8
Shared name:
Owner:              CWOLF-PC\cwolf
Auto-create:        Yes
State:              Running
Last start time:    6/12/2014 8:34:11 AM
Instance pipe name: np:\\.\pipe\LOCALDB#C86052DD\tsql\query
c:\>
c:\> sqlcmd -L

Servers:
    ;UID:Login ID=?;PWD:Password=?;Trusted_Connection:Use Integrated Security=?;
*APP:AppName=?;*WSID:WorkStation ID=?;

I finally figured it out!! the connect string is (localdb)\MSSQLLocalDB, e.g.:

$ sqlcmd -S \(localdb\)\\MSSQLLocalDB
1> select 'hello!'
2> go

------
hello!

(1 rows affected)    
75
votes

Use (localdb)\MSSQLLocalDB. That is the LocalDB instance intended for applications, independent of Visual Studio version.


Disregard my original answer: "With SQL Server 2014 Express LocalDB, use (localdb)\ProjectsV12. This works in both Visual Studio 2013 and SQL Server 2014 Management Studio." While ProjectsV12 will indeed give you a LocalDB instance, it's the wrong one, intended for use by SQL Server Data Tools.

20
votes

Use (localdb)\MSSQLLocalDBwith Windows Auth

2
votes

I was able to connect from SSMS using "(LocalDb)\Projects". That's the way it appears in VS2012 as well.

2
votes
 <add name="Default" connectionString="Data Source=(LocalDb)\MSSqlLocalDB; Initial Catalog=CRM_Default_v1; Integrated Security=True"
      providerName="System.Data.SqlClient"/>

your web.config files in visual studio under connectiionString or Go to View > SQL Server Object Viewer > Add Sql Server> add your server there

1
votes

You can connect with MSSMS to LocalDB. Type only in SERVER NAME: (localdb)\v11.0 and leave it by Windows Authentication and it connects to your LocalDB server and shows you the databases in it.

1
votes

Your Connection string should be like`

Data Source=(localdb)\ProjectsV13;Initial Catalog=master;Integrated Security=True;Connect Timeout=30;Encrypt=False;TrustServerCertificate=False;ApplicationIntent=ReadWrite;MultiSubnetFailover=False
0
votes

Suppose: SqlConnection connectionObj = new SqlConnection()

for : connectionObj.ConnectionString -> use server name : (localdb)\\MSSQLLocalDB.

Note: Double back slash

for : App.config -> use server name : (localdb)\MSSQLLocalDB

Note: Single back slash

0
votes

To locate a DB from SQL Server management studio can be done through browse - in the connect to database screen

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Also make sure a local database is installed during installation:

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