Here are two common pitfalls that you may encounter when it comes to working with dates, specifically with week numbers and weekdays. The first is to mistake week numbers in SQL Server for ISO week numbers (which are the weeknumbers used in Sweden, for instance). The other is to make assumptions about which day of the week is the first. The good news is that these are relatively easy fixes.
Have you noticed how date conversions can seem a bit arbitrary at times? How a string value is translated to a date depends on a number of factors, including how you perform the conversion and what language settings you have set for your connection. But there are ways to limit your conversion headaches.