XPost: microsoft.public.sqlserver.programming   
   From: genew@ocis.net   
      
   Dear SQL'ers:   
      
        How do I force a condition based on multiple rows?  I want the   
   necessary rows to be entered in a batch.  As a simple example, what   
   would be the coding of the constraint in this case following?   
      
             create table Symmetric   
              (   
              a int not null,   
              b int not null   
              )   
      
        Constraint: If (x,y) is in Symmetric, then (y,x) is also in   
   Symmetric.   
      
        Anyone adding rows would have to do it in a batch:   
             insert into Symmetric   
              (a,b)   
             values   
              (3,5),   
              (5,3)   
      
        I am hoping that there is a simple answer that I am overlooking.   
   Right now, all I can think of is to scan both Symmetric and the batch   
   (Inserted).   
      
   Sincerely,   
      
   Gene Wirchenko   
      
   --- SoupGate-Win32 v1.05   
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