/Fill the array 
    for i := 0 to .... do         
    begin
      resarray[i].dts:=formatdatetime('dd.mm.yyyy hh:nn:ss',dt); //String
...
    end;
...
    ldr.DateFormat:='DD.MM.YYYY HH24:MI:SS';
    ldr.Column[1].DataSize:=21;
    ldr.Column[1].DateFormat:='DD.MM.YYYY HH24:MI:SS';


  for i := 0 to length(Resarray) - 1 do
  begin
...
    ldr.Column[1].SetData(Row, @Resarray[i].dts[1], length(Resarray[i].dts));
...

    Inc(Row);
    // We have filled the array, or we are at the end of the file: load it
    if (Row = Ldr.MaxRows) or (i = length(Resarray) - 1) then
    begin
      try
        Ldr.Load(Row);
      except
        on E:EOracleError do
        begin
          showmessage(E.Message + #13#10#13#10 +
...

create table HD_TIMESERIES_VALUES
(
  TS_ID   NUMBER(20) not null,
  VTIME   DATE not null,
  VALUE   NUMBER(10,3) default 0 not null,
  STATUS1 VARCHAR2(1),
  STATUS2 VARCHAR2(1),
  VDATUM  DATE,
  constraint PK_TIMESERIES_VAL primary key (TS_ID, VTIME)
)
organization index;

Type
   TDateValue= record
      dt: TDatetime;
      dts:string;
      value: double;
    end;


var resarray:Array of TDateValue;

var dt:TDatetime;
...
resarray[i].dt :=dt; //TDatetime
resarray[i].dts:=formatdatetime('dd.mm.yyyy hh:nn:ss',dt); //String
...

TDateValue= record
      dt: TDatetime;
      dts:string;
      value: double;
    end;

TDateValue= record
      dt:    TDatetime;
      dts:   ansistring;  //<-!!
      value: double;
    end;