Updating table from datatable

[zuhx]

I am trying to update a table from a datatable. The datatable is populated first from a text file and then I would like to get that data into a database datatable. However the code below does not work, part of it is I do not know how to associate the connection string to the data adapter. Also, is there anything else I need to do? Do I need to have separate Update, Insert, and Delete commands or is it possible to just call the Update command? ConnectToDb connection = new ConnectToDb().conn; //this returns a SqlConnection SqlDataAdapter da = new SqlDataAdapter(); da.Update(ds.Tables["TradeOrderFillsPre"]);

[Heath Stewart]

Reading the table into a DataTable and adding that to a DataSetis what I would recommend, but iterating over the list of values in the text file and using a simple SqlCommand with SqlParameters (so you declare the command one and parameterize it to simply change the values and call ExecuteNonQuery) would also be easy and more efficient. If you want to use the SqlDataAdapter, you must at least have the SelectCommand assigned to with a SqlCommand for your SELECT statement. In order to insert, update, or delete rows, however, you must have the InsertCommand, UpdateCommand, and DeleteCommand assigned on the SqlDataAdapter. You can use the SqlCommandBuilder with the SelectCommand if the command is simple enough (i.e., JOINs and other advanced statements are not supported). Also, the SelectCommand must be parameterized (see the SqlCommand.Parameters property). See the SqlDataAdapter class documentation in the .NET Framework SDK (installed by default with VS.NET, and available online from http://msdn.microsoft.com/netframework[^]) for more information and an example of how to use some of these classes.

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