Sql query to convert nvarchar to int

Question

I have to query for total amount of a column using an aggregate function. The column data type is NVARCHAR(MAX). How can I convert it to Integer?

I have tried this:

Answer 1

3600.00 is not integer so CAST via float first

sum(CAST(CAST(amount AS float) AS INT))

Edit:

Why float?

• no idea of precision or scale across all rows: float is the lesser evil perhaps
• empty string will cast to zero for float, fails on decimal
• float accepts stuff like 5E-02, fails on decimal