Database Design - Preventing duplications for "Room" table - database

Question

Hey everyone, I'm trying to create a database for a personal friend of mine and given my inexperience with developing databases I'm having difficulty trying to establish one I'm currently dealing with. Essentially, my is issue is with my "rooms" table which has an association with another table called "location"; The location is the is everything you would expect (buildingID, streetAddress,etc.), and Room has a foreign key containing the buildingId. I want my "rooms" table to have unique values for room numbers based on the buildingId.
To give you a clearer idea, I'll just c&p the script I'm using to create those tables.
CREATE TABLE [dbo].[Location](
[buildingId] [int] IDENTITY(1,1) NOT NULL,
[streetAddress] [varchar](50) NOT NULL,
[postalCode] [varchar](7) NOT NULL,
[province] [varchar](30) NOT NULL,
[city] [varchar](30) NOT NULL,
CONSTRAINT [PK_Location] PRIMARY KEY CLUSTERED
(
[buildingId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY],
CONSTRAINT [UN_postalCode] UNIQUE NONCLUSTERED
(
[postalCode] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY],
CONSTRAINT [UN_streetAddress] UNIQUE NONCLUSTERED
(
[streetAddress] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
CREATE TABLE [dbo].[Room](
[rmId] [int] IDENTITY(1,1) NOT NULL,
[roomNum] [varchar](10) NOT NULL,
[floor] [int] NOT NULL,
[capacity] [int] NOT NULL,
[permission] [bit] NOT NULL,
[buildingId] [int] NOT NULL,
CONSTRAINT [PK_Room_1] PRIMARY KEY CLUSTERED
(
[rmId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
SET ANSI_PADDING OFF
GO
ALTER TABLE [dbo].[Room] WITH CHECK ADD CONSTRAINT [FK_Room_Location] FOREIGN KEY([buildingId])
REFERENCES [dbo].[Location] ([buildingId])
GO
ALTER TABLE [dbo].[Room] CHECK CONSTRAINT [FK_Room_Location]
GO
Any help would greatly be appreciated.
Thanks.

Answer 1

A table level unique constraint?
ALTER TABLE dbo.Room WITH CHECK ADD
CONSTRAINT UQ_Room_RoomBuildingLocation UNIQUE (roomNum, buildingId)
This can be a unique index too which would allow INCLUDE columns