Insert Record(s) to a Table from Another Table

insert into TableDocument2(DocumentId, DeptId, a, b, c, d,e) 
select DocumentId, 9, f, g, h, i, NULL from TableDocument

Get the Sum of a Particular DataTable Column

Use the DataTable.Compute method: 

    DataTable table;
    table = dataSet.Tables["Orders"];

    // Declare an object variable. 
    object sumObject;
    sumObject = table.Compute("Sum(Total)", "EmpID = 5");

where "EmpID = 5" is a filter expression. 

Use empty string if filter expression is not needed.

Get "2 days before" Dates

Get "2 days before" dates
SELECT * FROM Table1 WHERE DATEDIFF(day, CURRENT_TIMESTAMP, SampleDateField) = 2; 

Another sample usage of DATEDIFF
SELECT DATEDIFF(day, CURRENT_TIMESTAMP, SampleDateField) as 'Days' from Table1

Convert PagedCollectionView to Original Source

ObservableCollection<SavedReport> obvColSavedReports = new ObservableCollection<SavedReport>();
                foreach (var savedReport in ((PagedCollectionView)dataGrid1.ItemsSource).SourceCollection)
                {
                    SavedReport sr = (SavedReport)savedReport;
                    if (sr.IsSelected)
                        obvColSavedReports.Add(sr);
                }


See the bold text above? That's it!

The 'Microsoft.ACE.OLEDB.12.0' provider is not registered on the local machine.

Problem Summary:
I am getting the above error when I'm trying to import data from excel file in the production server. But, import excel is working on my local machine.

Cause:
The server does not have the proper DLL installed.

Solution:
Install the Office System Driver: Data Connectivity Components in the server.