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databasedatabase-designdatabase-normalization

why this table is not in 1st normal form

Suppose i have given the following table and i am trying to determine it is in 1NF or not.

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

I have applied following rules and it all satisfied then why the table is not in 1NF ?

My applied conditions:

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
Solution

  • The table is in 1NF, since each relation composed by a set of rows with a unique "atomic" value for each attribute is in 1NF, see for instance the definition in wikipedia.

    Actually, the 1NF has only an historic interest, since it is now considered part of the definition of the relational model.