What common mistake do developers make with Integer and decimal casts, why does the mistake cause problems, and what is the safer approach?

What common mistake do developers make with Integer and decimal casts, why does the mistake cause problems, and what is the safer approach? One recurring problem with integer and decimal casts is applying it without understanding the boundary it protects. Assuming every cast changes the database column type; casting often changes the application's representation of the stored value rather than the SQL schema. In addition, Numeric casts help keep application-level types consistent when database values are strings or decimal representations. Safer engineering approach: keep the responsibility in the correct layer, use the framework's supported API, validate and authorize inputs, avoid hidden side effects, and verify the behavior with tests.