U can use Between clause or datediff will be best i feel because between will not include the startdate and enddate.

But i am not understanding you question. Each record in...

select * from [table_name] order by column1, column2,column3 should work (even if all the column datatype if varchar)

The answer for the question is YES. FROM clause can be used in UPDATE query. But the example query given is wrong.

something like this will work

update table1

set coulmn=a2.column...