Then we recreate the diagram to fix the problem on above diagram :
1. There’s no cardinality between entity BAGIAN and PROYEK. It should have been 1-N from BAGIAN to PROYEK. With logic : one BAGIAN may have many PROYEK, and one PROYEK may only have one BAGIAN.
2. The ternary relationship between entity PEGAWAI, PROYEK, & TANGGUNGAN seems strange.
It’s logical if the PEGAWAI has a relation with TANGGUNGAN (TANGGUNGAN be the weak entity because it’s dependant with the existence of the PEGAWAI). But if it’s also has a relation with PROYEK (be the ternary relationship), it may seems a little strange. It’s also supported with the existence of relation between PEGAWAI an PROYEK. Then why we must have a relation again with ternary relationship here? It seems irrational to me, so I delete the ternary relationship here, change them only with binary relationship (between entity PEGAWAI and TANGGUNGAN).
3. To determine the mapping later, we need to fix the relation PIMPIN between entity PEGAWAI and BAGIAN to gain the foreign key. So with the logic : one BAGIAN must be managed at least by one PEGAWAI, and one PEGAWAI must not managing one BAGIAN; we create the participation here partial-total from PEGAWAI to BAGIAN.
First Normal Form (1NF)
A table on the form said to be normal if I did not reside in the unnormalized form of a table, where there is a kind of field multiplication and field that allows a null (empty).
second Normal Form (2NF)
- Normal form 2NF met in a table if it meets the form of 1NF, and all the attributes than the primary key, have a full Functional Dependency on primary key
- We can see at the table of Pegawai at 1ST NORMALIZATION has the transitive dependency between it's entities.
Transitive dependencies:
NoPeg → TglLah
TglLah → Umur
So the table of pegawai can be :
third Normal Form (3NF)
3NF on the changes only at the Pegawai table, because there are non-primary key attribute is dependent on the primary key attribute is non other, in this case KDPos has Alm1 of attributes, so that we make a new table on the table so that the Pegawai is to be:
NoPeg → TglLah
TglLah → Umur
So the table of pegawai can be :
third Normal Form (3NF)
3NF on the changes only at the Pegawai table, because there are non-primary key attribute is dependent on the primary key attribute is non other, in this case KDPos has Alm1 of attributes, so that we make a new table on the table so that the Pegawai is to be:
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