Check if SQL user exists...

[lidds]

I have the following SQL code, but I want to check to see if the SQL user is already created before trying to run the create user code so as to avoid errors. Could someone tell me how I can do an if statement in SQL for this?

EXECUTE sp_detach_db @dbname = N'MRCS', 
   		     @skipchecks = N'TRUE'
GO

EXECUTE sp_attach_single_file_db @dbname   = N'MRCS', @physname = N'C:\Program Files\Ticodi\MRCS\Database\MRCS_Data.mdf'
GO

[COLOR="Red"]If user does not exist then do this code[/COLOR]
EXECUTE execute sp_addlogin @loginame    = N'MRCSAdmin',
	    @passwd      = 'dragnet',
	    @defdb       = N'MRCS',
	    @deflanguage = N'us_english'
GO
[COLOR="red"]Endif statement[/COLOR]

Thanks in advance

Simon

 

[giadich]

something like this?

Declare @User as varchar(20)

select @User=Username from table

if @user<>''
begin
--user exists
--do something
end
else
begin
--user does not exist
--do something else
end