second normal form 第二范式，第二正规形式
数据库 数据库理论 释文 second normal form, 2NF 第二范式
- irish system
- iris in, iris out
- iris lactea
- iris microphotometer
- Iris Murdoch
- Iris Nebula
- iris photometer
- iris pigment cell
- iris recognition
- iris shutter
- iris stroma
- Irja Ranne
- Irkestam Kuo'an
- Irkin
- Irkutsk
- IRLS
- IRM
- IRMA
- IRMPD
- IRNA
- Irnerius
- IRNSS
- iron
- iron and steel analysis
- Iron and steel E-commerce