As you know, integer data in SQL Server is shown without a thousands separator. But sometimes you want that comma every three digits. The following is a simple conversion that uses the style argument of the CONVERT function to insert commas every three digits:
SELECT CAST(CONVERT(varchar, CAST(123456 AS money), 1) AS varchar)
The trade-off is that you get a decimal back?in this example, the result is 123,456.00. With a little extra effort, you can strip off the .00 if you need to.