Error: Unable to Open Database Project in Visual Studio 2012:

Error: Unable to Open Database Project in Visual Studio 2012: This version of SQL Server Data Tools is not compatible with the database run time components installed on this.

To fix this problem you need to install SQL Server Data Tools – November 2012 update. 

then try opening same project, you will get instruction saying (needs migration) with project file,
To migrate your project you need to Right Click on the Project name and select “Reload Project”.

All done here.

Error: "No column name was specified for column 1 of 'SOURCE'" in SQL Server Merge statement

when I was working with Merge statement with SQL Server 2008 then while writing this I got this error and after couple of min i got the issues 

Declare

      @Id         Int = 10,

      @Name       Varchar(20) = 'Kesharwani',

      @Salary     Int = 30000

          

MERGE INTO [Temp] as TARGET

      USING (SELECT @Id,@Name,@Salary) AS

SOURCE ON TARGET.empId = SOURCE.empId

      WHEN MATCHED THEN

            UPDATE SET Name=SOURCE.Name, Salary =SOURCE.Salary

      WHEN NOT MATCHED THEN

            INSERT (empId,Name,Salary)

VALUES (SOURCE.empId,SOURCE.Name,SOURCE.Salary);

While running above query sometime I got this error: No column name was specified for column 1 of 'SOURCE'.

The problem in the above query the alias name not there on the columns in Select statement, to resolve this error above query can be written in following way

Declare

      @Id         Int = 10,

      @Name       Varchar(20) = 'Kesharwani',

      @Salary     Int = 30000

          

MERGE INTO [Temp] as TARGET

      USING (SELECT @Id AS empId,@Name AS Name,@Salary AS Salary) AS

SOURCE ON TARGET.empId = SOURCE.empId

      WHEN MATCHED THEN

            UPDATE SET Name=SOURCE.Name, Salary =SOURCE.Salary

      WHEN NOT MATCHED THEN

            INSERT (empId,Name,Salary)

VALUES (SOURCE.empId,SOURCE.Name,SOURCE.Salary);