Sorry, that should be   
      
   Relationships   
   Field1   RecordID (Meaningless Identifier)   
   Field2   PersonID - points to Persons record of this person   
   Field3   RelativeType - 1 = Father; 2 = Mother, 3 = Brother, 4 = Sister   
   Field4   RelativeID - points to PersonID of relative   
   Primary Key = RecordID   
   Secondary Index on PersonID + RelativeType + RelativeID (Unique)   
      
   You should also include son/daughter in the relative type.   
      
   In Paradox, I would make PersonID and RecordID fields meaningless long   
   Integers, in a MS SQL database a GUID would be suitable. The RecordID   
   field identifies a unique relationship of one person to one other   
   person. You wouldn't necessarily use this in your logic but Paradox   
   requires a unique primary key to have secondary indexes. You could, of   
   course, have a primary key of PersonID + Relative Type + RelativeID as a   
   compound key.   
      
   It's the PersonID key in the Persons table that has a relationship to   
   the PersonsID field in the Relationships table (1 -->>M) via the   
   secondary index (this links all immediate relatives 1 generation up, one   
   down and one sideways), and the RelativeID field in the Relationships   
   table relates back (1 --> 1) to the PersonID of the relative via the key   
   of the Persons table.   
      
   Through recursion, you can step through the database up, sideways or   
   down for as many levels as you want.   
      
   MichaelR@niemand.org wrote:   
   > Hi,   
   > yes it's recursion. But I suppose more than one level. I would take it   
   > as fas as plausible data takes me.   
   > In the Table Relationships.Field1 (PersonsID) which field type do you   
   > take? That is my main problem.   
   >   
   >   
      
      
      
   --   
   Tom Krieg   
      
   ---------------   
   http://www.krieg.com.au   
   Please use the contact page to contact me via email   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)