문제

The table below is from a tutorial where the tables are in 3rd normal form. But if I insert information into the table PROJECT as follows:

projectCode  projectDescr  customerNo

1            Apples        21

1            Apples        22

Didn't I lose the 3NF cos the projectcode and projectdescr ends up repeating since 2 customers could possibly have the same project?

So my question is whether the table in the image below is in 3NF. And does the above problem even exists or I am looking at it wrongly? I am setting up my own table but before that I am trying to get the 3NF understanding right. Please help. Thanks.

The table from the tutorial:

enter image description here

도움이 되었습니까?

해결책

The assumption in the example would be that the relationship between PROJECT and CUSTOMER is many to one. A customer may have multiple projects but each project applies to only one customer. If you want a project to apply to multiple customers, then you need to split out another project_customer table that just contains a project and customer key for each row.

라이센스 : CC-BY-SA ~와 함께 속성
제휴하지 않습니다 StackOverflow
scroll top