SQLServer: How to sort table names ordered by their foreign key dependency

Question

The following SQL separates tables according to their relationship. The problem is with the tables that sort under the 3000 series. Tables that are part of foreign keys and

Answer 1

Thank you for a working solution NXC. You put me on the right track to solve the problem using a recursive CTE.

WITH 
  TablesCTE(TableName, TableID, Ordinal) AS
  (
  SELECT 
    OBJECT_SCHEMA_NAME(so.id) +'.'+ OBJECT_NAME(so.id) AS TableName,
    so.id AS TableID,
    0 AS Ordinal
  FROM dbo.sysobjects so INNER JOIN sys.all_columns ac ON so.ID = ac.object_id
  WHERE
    so.type = 'U'
  AND
    ac.is_rowguidcol = 1
  UNION ALL
  SELECT 
    OBJECT_SCHEMA_NAME(so.id) +'.'+ OBJECT_NAME(so.id) AS TableName,
    so.id AS TableID,
    tt.Ordinal + 1 AS Ordinal
  FROM 
    dbo.sysobjects so 
    INNER JOIN sys.all_columns ac ON so.ID = ac.object_id
    INNER JOIN sys.foreign_keys f 
      ON (f.parent_object_id = so.id AND f.parent_object_id != f.referenced_object_id)
    INNER JOIN TablesCTE tt ON f.referenced_object_id = tt.TableID
  WHERE
    so.type = 'U'
  AND
    ac.is_rowguidcol = 1
)  
SELECT DISTINCT 
  t.Ordinal,
  t.TableName
  FROM TablesCTE t
  INNER JOIN 
    (
    SELECT 
      TableName as TableName,
      Max (Ordinal) as Ordinal
    FROM TablesCTE
    GROUP BY TableName
    ) tt ON (t.TableName = tt.TableName  AND t.Ordinal = tt.Ordinal)
ORDER BY t.Ordinal, t.TableName

For thoose wondering what this is useable for: I will use it to safely empty a database without violating any foreign key relations. (By truncating in descending order) I will also be able to safely fill the tables with data from another database by filling the tables in ascending order.