This query listed tables that have no foreign keys, meaning they are not referencing any table or are not on the "many" side of FK.

Query below lists something a little different - tables that are not referencing and are not referenced by other tables. Something I called Loner Tables. This diagram illustrates the concept:

Learn more about Loner Tables

Check out this summary article of FK queries for SQL Server.

Query

select 'No FKs >-' refs,
    fks.tab as [table],
    '>- no FKs' fks
 from
    (select schema_name(tab.schema_id) + '.' + tab.name as tab,
        count(fk.name) as fk_cnt
    from sys.tables as tab
        left join sys.foreign_keys as fk
            on tab.object_id = fk.parent_object_id
    group by schema_name(tab.schema_id), tab.name) fks
    inner join 
    (select schema_name(tab.schema_id) + '.' + tab.name as tab,
        count(fk.name) ref_cnt
    from sys.tables as tab
        left join sys.foreign_keys as fk
            on tab.object_id = fk.referenced_object_id
    group by schema_name(tab.schema_id), tab.name) refs
    on fks.tab = refs.tab
where fks.fk_cnt + refs.ref_cnt = 0

Columns

• refs - icon symbolizing lack of references by foregin key constraints
• table - name of the table with schema name
• fks - icon symbolizing lack of foregin key constraints

Rows

• One row represents one table
• Scope of rows: tables that are not related (not refererencing and not being referenced with foreign key constraints) with any table
• Ordered by schema table name

Sample results

List of Loner Tables in AdventureWorks: