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third-normal-form

Violation of 3NF if we use an auto-incremented identity column along with a PK

As it is said in the book of Database Solutions Second Edition written by Thomas Connolly and Carolyn Begg page 180: Third normal form (3NF) A table that is already in 1NF and 2NF, and in which the values in all non-primary-key columns can be worked out from only the primary key column(s) and no other columns. I have seen many scenarios where people use an identity column though they already have a primary key column in their table. A record can also be worked out from the identity column, so isn't it a violation of 3NF if we use an auto-incremented identity column along with a primary key in

2021-05-03 04:13:28    分类:问答    database-design   entity-relationship   database-normalization   third-normal-form