This question is pretty much similar to this one, but for SQL Server 2005 :
I have 2 tables in my database:
--'#' denotes the primary key
[Libraries]
#ID #Application Name
1 MyApp Title 1
2 MyApp Title 2
[Content]
#ID Application LibraryID Content
10 MyApp 1 xxx
11 MyApp 1 yyy
(the database is obviously much more complex and having this double key makes sense)
Each library is identified by its unique ID and Application name. I'm trying to ensure that each content is properly referencing an existing library.
When creating the constraint (using the Wizard) as
Primary key table Foreign key table
[Libraries] [Content]
ID ---> LibraryID
Application ---> Application
I have the following error:
The columns in table 'Libraries' do not match an existing primary key or UNIQUE constraint
Do you have any idea of what is going on? and if it's possible at all using SQL Server? (I can't modify the [Library] table at all)
Thanks a lot for your help!
This question is related to
sql
sql-server-2005
foreign-key-relationship
Note that the fields must be in the same order. If the Primary Key you are referencing is specified as (Application, ID) then your foreign key must reference (Application, ID) and NOT (ID, Application) as they are seen as two different keys.
I had the same problem and I think I have the solution.
If your field Application
in table Library
has a foreign key that references a field in another table (named Application
I would bet), then your field Application
in table Library
has to have a foreign key to table Application
too.
After that you can do your composed foreign key.
Excuse my poor english, and sorry if I'm wrong.
The Content
table likely to have multiple duplicate Application
values that can't be mapped to Libraries
. Is it possible to drop the Application
column from the Libraries
Primary Key Index and add it as a Unique Key Index instead?
The key is "the order of the column should be the same"
Example:
create Table A (
A_ID char(3) primary key,
A_name char(10) primary key,
A_desc desc char(50)
)
create Table B (
B_ID char(3) primary key,
B_A_ID char(3),
B_A_Name char(10),
constraint [Fk_B_01] foreign key (B_A_ID,B_A_Name) references A(A_ID,A_Name)
)
the column order on table A should be --> A_ID
then A_Name
; defining the foreign key should follow the same order as well.
Source: Stackoverflow.com