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Editorial Team
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Asked: 2026-05-15T11:42:47+00:00

I’m pretty new to databases and sql. I have a problem where I have

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I’m pretty new to databases and sql. I have a problem where I have two tables which both contain a foreign key to the primary key of the other. My problem is I have a large number of elements which can have multiple names in different languages, but MUST have a single primary name/language.
alt text http://img688.imageshack.us/img688/1121/11768540.png

Firstly, I want to know if this is possible, or should I just give up already? The obvious solution is to have an extra boolean field in the ElementName table to say IsDefaultName, but it adds some extra complexity for querying and updating. If this is the best solution, how do I constrain the ElementName table to not accept any submission if IsDefaultName is set and the table already has an entry with the same ElementId and IsDefaultName set (or would I need to query this manually)?

I’m attempting to use LINQ to SQL here. The code I’m using to attempt to insert new items throws an exception at SubmitChanges with The INSERT statement conflicted with the FOREIGN KEY constraint "FK_ElementName_Element". I can understand why this is, but wondering if there’s a fix/better solution.

var db = new MyDBDataContext();
var element = new Element();
var elementName = new ElementName() {
    ElementName1 = "MyElement",
    Language = "English",
};
element.ElementName = elementName;

db.Elements.InsertOnSubmit(element);
db.ElementNames.InsertOnSubmit(elementName);
db.SubmitChanges();
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1 Answer

  1. Editorial Team

    Solution 1

    element
------------------
element_id
~....

element_name
------------------
element_name_id
fk_element_id
name
language_id
is_default_name  Default ( 0 )

Trigger:
if ( ( select count ( 1 ) from element_name where is_default_name = 1 ) > 1 )
BEGIN
    raisError ( 'only 1 element_name may be marked is_default_name = true.', 16, 1 );
END

    Solution 2

    element
------------------
element_id ( pk )
~....

element_name
------------------
element_name_id ( pk )
fk_element_id
name
language_id

element_name_default
------------------
fk_element_id
fk_element_name_id
( pk - fk_element_id, fk_element_name_id )

    Solution 3

    element
------------------
element_id
fk_element_name_id_default NULL
~....

element_name
------------------
element_name_id
fk_element_id
name
language_id

order of code:
* Insert to element_name
* update of element

    I would stick with what you had, cause it is just fine, just:

    db.Elements.InsertOnSubmit(element);
db.ElementNames.InsertOnSubmit(elementName);
//I don't know this syntax to say
//  set the property of element.fk_element_name_id_default 
//  to the newly inserted elementName from above
db.Elements.?.?
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