hi..
Datareader behavior is read-only, forward only & fetches record one by one. if u want only one select statement then u can use datareader otherwise dataadapter. if u'r connection string is sqlserver then
SqlDataReader dr=cmd.ExecuteReader()
GridView providea arrangement of data from dataset in a XML format
GridView1.DataSource=<dataset object>.Tables["alias name of table in dataset"]
GridView1.DataBind()
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