SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 3)
    Function length (children 1)
     ExpressionList (children 1)
      Identifier name
    Identifier name
    Literal \'.\'
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.users
   Function notEquals (children 1)
    ExpressionList (children 2)
     Function position (children 1)
      ExpressionList (children 2)
       Identifier name
       Literal \' \'
     Literal UInt64_0
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier name