I have an established OleDbConnection that I want to use to populate a DataGridView. I can run SQL queries on the connection and see data sets, but I would like to present a view of that data in my grid. Also, I'd like to be able to only show a fouple of the columsn, but hold on to the full data set for later use.
Any pointers would be appreciated... Thanks.
Now, is it possible to restrict the columns that are displayed on the grid? Currently, it is displaying all columns from my table in the grid. I only want to show a couple of them...
I would suggest you filter your query to show the specific columns you would like to show :-)
or you could remove it from your dataGridView Columns:
this.theDataGridView.Columns.Remove(ColumnName);
// hide all columns & restore the ones we want to see
DataGridViewColumnCollection columns = userGrid.Columns;
foreach (DataGridViewColumn col in columns) {
col.Visible = false;
}
columns["firstNameCol"].Visible = true;
columns["lastNameCol"].Visible = true;
Now, I'm trying to commit the changes back to the database. I call AcceptChanges() on my data set, but it does not get saved. Any help here? Thanks!
you should use the Update() method on the Sql/OleDbDataAdapter - this will do it for you.
Also how do you know if the changes are saved or not? you need to refill the dataset to load the data back and re-bind it, it does not "auto update" the datagridview.
I have a grid and a set of text boxes that are bound to my table. The grid is read only. As I make changes in the text boxes. I'm able to move away and go back to a record, and my changes are there. I assumed it was being updated in the DataSet.
Is that correct?
is the textboxes bound to the grid? (in other words, is the textbox control in the grid?)
if its seperate, as I am thinking and reading your reply, the values will not be updated in the dataset, you would have to update this in some way.
If it was in a grid, it should automatically set the updated values in the dataset, settings its state to something like "to be updated" so when you call the data Adapters update() method, it will look at the rowstates to see which rows needing to be updated to the datasource (SQL) and execute the appropriate command for you.
How do I access the adapter for the data grid? Is it the same adapter that I used to execute the Fill command?
If I understand correctly, I need to update the data adapter, which will cause the data set to receive the updates and then AcceptChanges will update the database, correct?
// setup the internal data set
_dataSet = new DataSet();
// populate the users table
_dataAdapter = new OleDbDataAdapter("SELECT * FROM Users;", _db);
_dataAdapter.Fill(_dataSet, "Users");
// populate the time trials table
_dataAdapter = new OleDbDataAdapter("SELECT * FROM TimeTrials;", _db);
_dataAdapter.Fill(_dataSet, "TimeTrials");
// close the connection
_db.Close();
And here is a function I use to update the data when the dialog is closing:
_db.Open();
_dataAdapter.Update(_dataSet);
_dataSet.AcceptChanges();
_db.Close();
There is a problem with the second functoin... I'm getting an exception about an invalid table mapping.
Thanks for all your help so far... I feel so close!
take out the dataSet.AcceptChanges() and see what happens.
have you set some mapping before hand or in some area of code with the dataAdapter? make sure you clear the table mapping anyway (if you don't need them) by:
_dataAdapter.TableMappings.Clear();
I haven't changed the data set (knowingly) between these two function calls. If it is easier, I could send my full project (it is pretty small).
--jah
After creating the DataAdapter, I create a OleDbCommandBuilder on that adapter. Then, after calling Fill() on the adapter, I call GetUpdateCommand() on the command builder. During the save part, I just call dataSet.GetChanges, then use the adapter to Update using the changes (with the correct table name). That seems to make thing work.
