when use SQLBULKCOPY if record exist how can i update ?

Question

hello everybody, 

 

im using excel table import to sql,

 

if i already have a same record how can i update it then continue import other data ?  

 

DataTable dt = new DataTable();

dt.Columns.Add("SHEET", typeof(int));

dt.Columns.Add("DATE", typeof(DateTime));

dt.Columns.Add("DATA", typeof(string));

dt.Columns.Add("CODE", typeof(string));

IRow excelRow = default(IRow);

excelRow = sheet.GetRow(0);

for (int Cel = 1; Cel <= excelRow.LastCellNum - 1; Cel++)

{

var cellValue = excelRow.GetCell(Cel);

for (int k = 1; k <= sheet.LastRowNum - 1; k++)

{

string code = cellValue.ToString();

var date = sheet.GetRow(k).GetCell(0);

var value = sheet.GetRow(k).GetCell(Cel);

string dates = date.ToString();

string values = value.ToString();

dt.Rows.Add(b, dates, values, code);

}

}

cnn.Open();

SqlBulkCopy bulkCopy = new SqlBulkCopy(cnn);

bulkCopy.DestinationTableName = "RMQ_DATA";

bulkCopy.WriteToServer(dt);

cnn.Close();