SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function count (children 1)
     ExpressionList
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 3)
          ExpressionList (children 1)
           Function throwIf (children 1)
            ExpressionList (children 1)
             Function notEquals (children 1)
              ExpressionList (children 2)
               Function count (children 1)
                ExpressionList
               Literal UInt64_2
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier t6
          ExpressionList (children 1)
           Identifier a