Hi guys,
I am having severe performance problems with sql server. I Have a sales table(sales) with 11 million rows. I have another table that accumulates the sales data into months for the last 2 years(month_sales). In the sales table I have a field to indicate that the record has been added to the calculated table(month_sales). When I start updating the month_sales and the field in sales table the whole sql server comes to a stand still. Is this the best way to do this or is there any other way to create calculated fields.

TIA