mysql - 2NF database Normalization -

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good day-

i'm working on task in have create data model on basis of following information.

your task create model storing following information: list of albums , album art each (image files), tracks 1 album, band’s record label or labels, genre, , band members.

i have created 5 tables far. , have cover normalization part i'm confused it.one of table have created has following columns , data.

bandmember

  1. bandmemberid - auto increment
  2. bandladelid - fk
  3. realname
  4. nickname
  5. memberphoneno
  6. memberrole
  7. memberactive
  8. memberdob
  9. memberage

and table has following data far.

enter image description here

for resolving have removed comma separated values , add each row data. it's this.

enter image description here

could please guide me how can split table , remove problem (if normalization exist)? because i'm confused primary key here. examples referred on internet based on age column. i'm not getting examples. in advance.

your step split row multivalued attribute multiple rows looks step resolve repeating groups achieve 1nf. however, in transformation, each new row gets copy of corresponding values in original. auto-increment column incremented new row, , hence 2nd table different problem, , not 1nf version of first.

the 1st table, transformed 1nf, have 2 rows, both bandmemberid values of 1 , using (bandmemberid, memberrole) candidate key. since non-prime attributes depend on bandmemberid, that's partial dependency. copying (bandmemberid, memberrole) separate table , removing memberrole bandmember table give 2nf schema. don't give functional dependencies i'm not sure if schema in 3nf well.


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