Copy prior month value and insert into new row
问题 Here is an example of the current table I have: 1) Table name: TotalSales Name Year Month Sales ------ ---- ----- ----- Alfred 2011 1 100 What I want to do is create a table like this, add a new row(Prior month sales): 2) Table name: TotalSales Name Year Month Sales Prior month sales ------ ---- ----- ----- ----------------- Alfred 2011 2 110 100 Not sure how to this, but this is what I have been working on: SELECT Name, Year, Month, Sales, Sales as [Prior Month sales] FROM TotalSales WHERE