any changes made in the parent table are automatically updated in a child table. Referential integrity is always maintained i.e.Data can be retrieved easily due to the explicit links present between the table structures.The data in a hierarchical pattern must be accessed through a single path only.parent-child relationship must be present. The data should be in a hierarchical pattern i.e. ![]() It is useful where the following two conditions are met: A hierarchical database is also used for Windows Registry in the Microsoft Windows operating system. It is used in applications where high performance is required such as telecommunications and banking. Today, it is used mainly for storing file systems and geographic information. The uses of the database model are as explained here.Ī Hierarchical database model was widely used during the Mainframe Computers Era. This depicts one- to- many relationships. ![]() B1 and B2 also have two children C1, C2 and C2, C3 respectively. ![]() B1 and B2 are their child or subdirectories.
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