SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 2)
    Identifier t1.pk
    Identifier t2.x.y
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier test1 (alias t1)
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      TableIdentifier test2 (alias t2)
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier t1.pk
        Identifier t2.pk
