Computer Sciene of Udayana State University

April 26, 2009

1NF to 2NF

Filed under: Computer Science — ignaga @ 2:11 AM
  • Identify FD’s in the relation.
  • If partial dependencies exist on the primary key remove them by placing them in a new relation along with copy of their determinant.

EMP_PROJ(SSN, Pnum, Hours, Ename, Pname, Ploc)

{SSN,Pnum}–>Hours, SSN–>Ename, Pnum–>{Pname, Ploc}

EMP_PROJ decomposed into:

EMPLOYEE(SSN, Pnum, Hours) , {SSN,Pnum}–>Hours

WORKS_ON(SSN, Ename) , SSN–>Ename

PROJECT(Pnum,Pname, Ploc) , Pnum–>{Pname, Ploc}

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