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2nd normal form

Relation (table) is in 2NF if
iddatereceiver idreceiver surnamedeliverer namedeliverer address
112th December3NowakFastTransWadowice
214th December4NowakGuliwerWarszawa
table in 1NF At above table primary key is `id`, `receiver_id`, `deliverer_name` and no attribute is fully functional dependent from primary key. To normalize above relation to 2NF we have to divide it into following tables:
iddatereceiver_iddeliverer_name
112th December3FastTrans
214th December4Guliwer
sub-relation with deliverers at 2NF
receiver_idreceiver_surname
3Nowak
4Nowak
sub-relation with receivers at 2NF
receiver_namereceiver_address
FastTransWadowice
GuliwerWarszawa
sub-realtion with deliverers at 2NF Above sub-relations may be joined together logically through foreign keys. [ wróć na górę strony ]