c#에서 오라클 커넥션을 DataTable로 적재하는데 성능이 너무 안나오네요 도움 부탁드립니다.4

자바개발자인데... 뜬금없이 C#을 좀 써야 할 일이 생겼습니다.

오라클에서 쿼리를 날려서 DataTable로 넣는데 성능이.. -.-;;;

쿼리는 149ms만에 돌았는데 DataTable로 넣는데 거의 10초가 걸립니다.

제가 뭔가 잘 못하고 있는거 같은데 뭔지를 모르겠습니다 도움 부탁드립니다.

using (OracleConnection conn = new OracleConnection(_sourceConnString))

{

    conn.Open();

    using (OracleCommand cmd = conn.CreateCommand())

    {                        

        cmd.CommandText = sql;

        using (OracleDataReader dr = cmd.ExecuteReader())//149ms, 32rows

        {

            //XmlDocument doc = DataReadertoDataXML(dr);

            DataTable dt = dataset.Tables.Add("transdata");

            dt.BeginLoadData();

            dt.Load(dr, LoadOption.Upsert);//8,987ms

            dt.EndLoadData();

            _resultGridView.DataSource = dt;

            SetStatus(dt.Rows.Count + "건의 데이터가 조회되었습니다.");

        }

    }

    conn.Close();

}

데이터 구조는

<?xml version="1.0" standalone="yes"?>

<xs:schema id="NewDataSet" xmlns="" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">

  <xs:element name="NewDataSet" msdata:IsDataSet="true" msdata:MainDataTable="selectdata" msdata:UseCurrentLocale="true">

    <xs:complexType>

      <xs:choice minOccurs="0" maxOccurs="unbounded">

        <xs:element name="selectdata">

          <xs:complexType>

            <xs:sequence>

              <xs:element name="RECHISTSEQ" type="xs:decimal" minOccurs="0" />

              <xs:element name="RECITEMNO" type="xs:decimal" minOccurs="0" />

              <xs:element name="INSTCD" type="xs:string" minOccurs="0" />

              <xs:element name="FSTLEVLITEMCD" type="xs:string" minOccurs="0" />

              <xs:element name="FORMCD" type="xs:string" minOccurs="0" />

              <xs:element name="FORMDEGNSEQ" type="xs:decimal" minOccurs="0" />

              <xs:element name="DEGNITEMNO" type="xs:decimal" minOccurs="0" />

              <xs:element name="DEGNITEMCD" type="xs:string" minOccurs="0" />

              <xs:element name="DEGNITEMLEVLCD" type="xs:string" minOccurs="0" />

              <xs:element name="RECTERMCD" type="xs:string" minOccurs="0" />

              <xs:element name="RECTERMNM" type="xs:string" minOccurs="0" />

              <xs:element name="RECREFCD" type="xs:string" minOccurs="0" />

              <xs:element name="RECITEMNM" type="xs:string" minOccurs="0" />

              <xs:element name="RECCNTS" type="xs:string" minOccurs="0" />

              <xs:element name="COLNO" type="xs:string" minOccurs="0" />

              <xs:element name="ROWNO" type="xs:string" minOccurs="0" />

              <xs:element name="SUPDEGNITEMNO" type="xs:decimal" minOccurs="0" />

              <xs:element name="DEGNITEMKIND" type="xs:string" minOccurs="0" />

              <xs:element name="DEGNITEMLEVLNO" type="xs:decimal" minOccurs="0" />

              <xs:element name="DEGNITEMNM" type="xs:string" minOccurs="0" />

              <xs:element name="EXTDEGNITEMLEVLCD" type="xs:string" minOccurs="0" />

              <xs:element name="RECTERMFLAG" type="xs:string" minOccurs="0" />

              <xs:element name="DEGNUNITCD" type="xs:string" minOccurs="0" />

              <xs:element name="FSTRGSTRID" type="xs:string" minOccurs="0" />

              <xs:element name="FSTRGSTDT" type="xs:dateTime" minOccurs="0" />

              <xs:element name="LASTUPDTRID" type="xs:string" minOccurs="0" />

              <xs:element name="LASTUPDTDT" type="xs:dateTime" minOccurs="0" />

              <xs:element name="MIG" type="xs:dateTime" minOccurs="0" />

            </xs:sequence>

          </xs:complexType>

        </xs:element>

      </xs:choice>

    </xs:complexType>

  </xs:element>

</xs:schema>

입니다.

특이점으로는 CLOB컬럼이 하나 있지만 실제 데이터는 굉장히 작습니다.VARCHAR2(4000)으로 충분히 처리될 정도입니다.