Tinkerbell Glitter
[250121] ์ฟผ๋ฆฌ์…‹(QuerySet)์ด๋ž€?
Back End ๐Ÿ“ฒ/Django โ›“๏ธ
QuerySet์ด๋ž€?1. QuerySet ์ •์˜QuerySet์€ Django ORM(Object-Relational Mapping)์˜ ํ•ต์‹ฌ ์š”์†Œ๋กœ, ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์—์„œ ํŠน์ • ์กฐ๊ฑด์— ๋งž๋Š” ๊ฐ์ฒด์˜ ๋ฆฌ์ŠคํŠธ๋ฅผ ํ‘œํ˜„ํ•œ๋‹ค.๋ฐ์ดํ„ฐ๋ฅผ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์—์„œ ๊ฒ€์ƒ‰ํ•  ๋•Œ ๊ฒŒ์œผ๋ฅด๊ฒŒ ํ‰๊ฐ€(Lazy Evaluation) ๋œ๋‹ค. ์ฆ‰, ์ฟผ๋ฆฌ๊ฐ€ ์‹ค์ œ๋กœ ์‹คํ–‰๋˜๊ธฐ ์ „๊นŒ์ง€ ๋ฐ์ดํ„ฐ๋ฒ ์ด์Šค์™€ ์ƒํ˜ธ์ž‘์šฉํ•˜์ง€ ์•Š๋Š”๋‹ค.2. QuerySet ์ƒ์„ฑ ๋ฐฉ๋ฒ•1) ๊ธฐ๋ณธ QuerySet ์ƒ์„ฑfrom myapp.models import Book# ์ „์ฒด ๊ฐ์ฒด ์กฐํšŒbooks = Book.objects.all()2) ํ•„ํ„ฐ๋ง์„ ํ†ตํ•œ QuerySet# ํŠน์ • ์กฐ๊ฑด์— ๋งž๋Š” ๋ฐ์ดํ„ฐ๋งŒ ๊ฐ€์ ธ์˜ค๊ธฐbooks_by_author = Book.objects.filter(author="John Doe")..