The Function

function getEnrollmentByStudentIdAndCourseId(   studentId: string,   courseId: string ) {   // fetch logic   return result; } 

The Mistake

Believe it or not this function caused me a day of debugging. Because of the way I was calling it like this.

const studentId = "ID"; const courseId = "ID";  const enrollment = getEnrollmentByStudentIdAndCourseId(courseId, studentId); 

I was passing the arguments in the wrong order. The function signature was getEnrollmentByStudentIdAndCourseId(studentId, courseId) but I was calling it with getEnrollmentByStudentIdAndCourseId(courseId, studentId).

The reason why i took so long debugging it was because function was still returning a result even though the arguments were in the wrong order, but it was the wrong result. I think this is ultimately a mistake i made by writing a bad prisma query that caused it.

The Adjustment

make the argument passing more explicit by using object

type Args = {   courseId: string;   studentId: string; };  function getEnrollmentByStudentIdAndCourseId({ courseId, studentId }: Args) {   // fetch logic   return result; } 

Ever since then, when I have a function that takes multiple arguments of the same type like IDs, I started to use object destructuring to make the argument passing more. And also like… made better prisma queries.

I hope this helps you avoid the same mistake I made. Happy coding!