SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 4)
   ExpressionList (children 2)
    Identifier part_name
    Identifier read_rows
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      TableIdentifier system.part_log
   Function and (children 1)
    ExpressionList (children 3)
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier database
       Function currentDatabase (children 1)
        ExpressionList
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier table
       Literal \'t_modify_to_nullable\'
     Function equals (children 1)
      ExpressionList (children 2)
       Identifier event_type
       Literal \'MutatePart\'
   ExpressionList (children 1)
    OrderByElement (children 1)
     Identifier part_name
