Select max int from varchar column

Question

I am trying to retrieve the largest number from a varchar column that includes both numbers and strings. An example of the data I\'m working with:

BoxNumber

Answer 1

Well, in the intervening 11 years since this question was asked, SQL Server gained the try_cast function, which returns null rather than throwing an error if the conversion doesn't succeed. So in current versions of SQL Server, a valid answer is

select max(try_cast(BoxNumber as int)) from theTable