Hi,

hope this is better! Please could you help me by suggesting corrections?

CREATE PROCEDURE [dbo].[usp_UsersRegistration]

@ID VARCHAR(10),

@Username VARCHAR(50),

@Password VARCHAR(50)

AS

MERGE [dbo].[Users] AS [Target]

USING (SELECT @Username, @Password)

AS [Source] ( [Username], [Password] )

ON [Target].[Username] = [Source].[Username]

ON [Target].[Password] = [Source].[Password]

WHEN MATCHED THEN

UPDATE SET [ID] = [Source][ID],

[Username] = [Source].[Username],

[Password] = [Source].[Password]

RETURN -1

WHEN NOT MATCHED THEN

INSERT ( [ID], [Username], [Password] )

VALUES ( [Source].[ID], [Source].[Username],

[Source].[Password];

RETURN 0

GO