prisma 검색시 undefined 조건은 필터링을 하지 않겠다는 의미와 같다

Note: Using undefined as the value of any key in a Prisma Client query's parameter object will cause Prisma ORM to act as if that key was not provided at all.

참고링크: https://www.prisma.io/docs/orm/prisma-client/special-fields-and-types/null-and-undefined

따라서, 아래 두 쿼리는 전혀 다른 동작을 보인다:

null => 정확히 null이 담겨있는 엔티티를 가져온다

const users = await prisma.user.findMany({
  where: {
    name: null,
  },
})

undefined => name 필터링을 하지 않겠다.

const users = await prisma.user.findMany({
  where: {
    name: undefined,
  },
})

// equivalent as

const users = await prisma.user.findMany()