DateTime's representation in milliseconds?

Question

I have a SQL-server timestamp that I need to convert into a representation of time in milliseconds since 1970. Can I do this with plain SQL? If not, I\'ve extracted it into

Answer 1

SELECT CAST(DATEDIFF(S, '1970-01-01', SYSDATETIME()) AS BIGINT) * 1000

This does not give you full precision, but DATEDIFF(MS... causes overflow. If seconds are good enough, this should do it.