MySQL truncating security issue

I have noticed a security issue with a MySQL FUNCTION.

I have a built in FUNCTION which takes a BIGINT as a parameter.

If the value '7xs8d' is sent, the value is truncated to 7 and the function proceeds like it has a valid value.

I realized that I need to detect a truncated value and error.

How do you either prevent the truncation or detect that it has been truncated in a MySQL built开发者_C百科 in FUNCTION?