假设我给了下面的表格,我试图确定它是在1NF或不是。为什么这个表格不是第一种正常形式
Table:
Mem_id mem_name phone email Book_num Book_titl Author_nam publication edition
100 smith 12443 eml1 200 physics john MACGROW 1ST
201 math martin MACGROW 2ND
101 hena 1020 eml2 200 physics john MACGROW 2ND
102 moon 2020 eml3 204 new java korth ALPHA 4TH
我已经应用以下规则,它都满足,那么为什么表不在1NF?
我的应用的条件:
1.values of each attribute is atomic/ Only one value per column
2.no two rows are identical
3.every column has unique name
4.all entries in any column must be same type
谁告诉你它不是? –