5 replies to this topic

[access@123]

hi
i have a window application, wherein i have to choose the database,its table and rowfields present in the table at runtime. Now i want to remove all the duplicates from database. my database is access and whichever row field the user chooses the duplicates should be removed leaving the latest updated row. Please help me my code is as below..

string str = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + txtPath.Text; 
OleDbConnection con = new OleDbConnection(str); 

string t = "select * from " + cmbtables.SelectedItem.ToString(); 
OleDbDataAdapter adt = new OleDbDataAdapter(t, str); 
con.Open();
DataSet ds = new DataSet(); 


adt.Fill(ds);

DataTable dt = ds.Tables[0]; 
con.Close();
dt = RemoveDuplicateRows(dt, cmbRow.SelectedItem.ToString());


private DataTable RemoveDuplicateRows(DataTable dTable, string colName)
{
Hashtable hTable = new Hashtable();
ArrayList duplicateList = new ArrayList();
foreach (DataRow drow in dTable.Rows)
{
if (hTable.Contains(drow[colName]))
duplicateList.Add(drow);
else
hTable.Add(drow[colName], string.Empty);
}
foreach (DataRow dRow in duplicateList)
dTable.Rows.Remove(dRow);
return dTable;
}

when i use datatable.update it is giving me error hoping for your co-operation
Thank you

Edited by WingedPanther, 12 October 2008 - 01:48 PM.
add code tags

[WingedPanther]

Without knowing the table structure of your database it will be a little tough to help you. For example, do you have a time-stamp in your table? How about a GUID? If you're going to use a database, you should really be using SQL to handle the deletions/updates.

[access@123]

hi thanks for your response, however in my table there is no timestamp column. let me explain once more the scenario, i have a desktop application wherein i select the database it can be any database and then i have to select the table and then the row fields present in the table. so it can be any table or any row field which user selects at runtime.

[WingedPanther]

It sounds like you're writing a cleanup utility for arbitrary badly designed databases, correct?

[access@123]

WingedPanther said:

It sounds like you're writing a cleanup utility for arbitrary badly designed databases, correct?

yes absolutely correct so if possible help me in writing this utility....