Logical Database Design

Creating a database logical design is one of the first important steps in designing a database. There are four logical database models that can be used hierarchical, network, relational, or object-oriented.
1.Hierarchical:
The first important logical database model. Still found in many mainframe-based, legacy systems. Records are arranged in a top-down parent/child structure. Each child can be related to only one parent
2.Network
Developed to overcome the limited scope of the hierarchical model. Similar to the hierarchical model only there's no parent/child distinction. …