The integer value for the first day of the month is even easier:
SELECT BOM = @ThisYear * 10000 + @ThisMonth * 100 + 1,
but you must CAST it to char(8) before storing it in a date/datetime column.
DECLARE @BOM datetime
SELECT @BOM = CAST(@ThisYear * 10000 + @ThisMonth * 100 + 1 AS char(8))
SELECT @BOM
SQL DBA,SQL Server MVP(07, 08, 09) "It's a dog-eat-dog world, and I'm wearing Milk-Bone underwear." "Norm", on "Cheers". Also from "Cheers", from "Carla": "You need to know 3 things about Tortelli men: Tortelli men draw women like flies; Tortelli men treat women like flies; Tortelli men's brains are in their flies".