์—ฐํ˜œ์Šฌ 2021. 10. 10. 03:53

superkey : tuple์„ ํŠน์ •์ง€์„ ์ˆ˜ ์žˆ๋Š” attribute ๋˜๋Š” attribute์˜ ์ง‘ํ•ฉ ๋ชจ๋‘

 

candidate key: primary key๊ฐ€ ๋  ์ˆ˜ ์žˆ๋Š” ํ›„๋ณดํ‚ค๋กœ, tuple์„ ํŠน์ •์ง€์„ ์ˆ˜ ์žˆ๋Š” super ํ‚ค ์ค‘ ์ตœ์†Œ์ธ ๊ฒƒ(๋ถˆํ•„์š”ํ•œ ๊ฒƒ ๋บ€ ๊ฒƒ)

primary key : candidate key ์ค‘ ํ•˜๋‚˜

 

foreign key : ๋‹ค๋ฅธ relation์˜ pk๋ฅผ ์ฐธ์กฐํ•œ key