How to delete row or the whole Sheet using OLEDB and C# .Net

i want to delete row in excel file from query because when i insert data in 2nd time, data is not insert in proper place for example

INSERT INTO OPENROWSET('Microsoft.Jet.OLEDB.4.0', 
'Excel 8.0;Database=D:\TestDB\first.xls;', 
'SELECT cid, ClassName FROM [Sheet1$]') 
SELECT cid, classname FROM Class
GO

now rows insert from top row, it's fine. now i want to execute this again. i want to delete old data and insert new data. for this purpose i use this query

 update openrowset('Microsoft.Jet.OLEDB.4.0', 
'Excel 8.0;Database=D:\TestDB\first.xls;', 
'SELECT cid, ClassName FROM [Sheet1$]') 
set cid=null,
classname=null

INSERT INTO OPENROWSET('Microsoft.Jet.OLEDB.4.0', 
'Excel 8.0;Database=D:\TestDB\first.xls;', 
'SELECT cid, ClassName FROM [Sheet1$]') 
SELECT cid, classname FROM Class
GO

Now insert from 60 row not in top row. I want to insert again in top row. i want to also delete and add sheet from query

please help thanks