判断 方法为： OleDbConnectioncon=newOleDbConnection(连接字符串); stringname=test; con.Open(); OleDbCommandcmd=newOleDbCommand(selectcount(*)fromstudentDetailswheresname='name',con); intcount=Convert.ToInt32(cmd.ExecuteScalar()); con.Close(

判断方法为：

OleDbConnection con=new OleDbConnection("连接字符串");
string name="test";
con.Open();
OleDbCommand cmd=new OleDbCommand("select count(*) from studentDetails where sname='"+name+"'",con);

int count=Convert.ToInt32(cmd.ExecuteScalar());
con.Close();
if (count>0)
{
//说明记录存在..
}
else
{
//说明记录不存在..
}