row delete can't be effect on database

ramesh rammi

My code worked properly but row can't be delete from database table.in datatable row deleted.after call the .da.update(ds,"student") need to effected database table but row can't be deleted in database table

my code:

SqlConnection con = new SqlConnection("Data Source=AMMA-PC\\SQLEXPRESS;Initial Catalog=E_learn;Integrated Security=True");
string query="select * from Student where sid="+TextBox1.Text;
SqlDataAdapter da = new SqlDataAdapter(query, con);
SqlCommandBuilder br = new SqlCommandBuilder(da);
DataSet ds = new DataSet();
da.Fill(ds, "Student");
if (ds.Tables[0].Rows.Count > 0)
{
DataTable dt = ds.Tables[0];
DataColumn[] keyColumns = new DataColumn[1];
keyColumns[0] = dt.Columns["sid"];
dt.PrimaryKey = keyColumns;
DataRow dr = dt.Rows[0];
dt.Rows.Remove(dr);
da.Update(ds, "Student");
Response.Write("deleted successfully");
}

I think u have doubt about delete row. how should know row deleted from datatable in dataset. i had verfied through breaking points keys like F10,F11.at the time in dataset visualizer shows before call da.update(ds,"Student") i have row. after call da.update(ds,"Student").dataset visualizer shows row deleted but database does not effected.row can't be deleted from database . what is the problem

i don't know. please help me.

Thank u

4 Replies

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Mageshwaran R6y ago
Hi,
Please refer the below link, it might helps you
https://www.c-sharpcorner.com/UploadFile/009464/make-edit-update-and-delete-operation-in-gridview-in-Asp-Net/
Rafnas T P8y ago
hi,

you have removed row from datatable dt not from dataset ds,

try instead of dt.Rows.Remove(dr);

change

ds.Tables[0].Rows.Remove(dr);
Amit Gupta8y ago
Following points tk be considered
1. When you have to delete the first row then why using select statement and do various stuff and then deleting the row?

You can simply use delete statement based on your sid

Delete from student where sid= textboxValue;

2. Database don't refresh its data, you have to press ctrl+r to reload the data for any conflict changes

3. If you are looking at your gridview then rebind the data again after deletion.

Do let me know, on which points your issue lies.
Nitin Sontakke8y ago
Never ever have used this approach in my life and is unlikely to use it ever (retiring in about next 7 years now!)

Have a look at the following link. Do you have to use this method?

https://msdn.microsoft.com/en-us/library/system.data.datatable.acceptchanges(v=vs.110).aspx