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By storing related data in separate tables and linking them through common fields, the relational model
              ensures efficient data organisation, retrieval, and manipulation. This model’s flexibility and scalability make
              it one of the most prevalent and versatile database models, used across various industries and applications.
              The difference among hierarchical, network and relational data models is shown in the following table:


                     Feature        Hierarchical Data Model       Network Data Model         Relational Data Model
               Structure           Tree-like structure with     Similar to the hierarchical   Table-based structure
                                   parent-child nodes           model but with more         with rows and columns
                                                                flexible relationships.

               Data                Records linked by            Records linked by multiple  Data stored in tables
               Representation      hierarchical paths           paths

               Parent-Child        Each child has only one      Each child can have         Relationships established
               Relationship        parent                       multiple parents            via common fields

               Flexibility         Less flexible, rigid structure  More flexible, complex   Highly flexible, easy to
                                                                structure                   modify

               Data Integrity      Enforced through hierarchy   Maintained through          Enforced through
                                                                complex relationships       constraints and keys


                 ELEMENTS OF DATABASE

              Data in a DBMS is generally kept in a tabular format and is organised by fields, records and files. A field
              represents a single type of related information; a record is a complete set of values stored under fields,
              whereas a file is a collection of records.

                Table: Tables are the basic structure of a database where data is stored. Each table consists of rows and
                 columns. A table is a collection of logically related records.
                Generally,  a  column  represents  a  field  that  contains  information  of  a  particular  type,  whereas  a  row
                 represents records that contain information of the related fields.
                Columns/Fields/Attributes: A column is a set of data values of a particular simple type, one for each row
                 of the table. For example, age, name, address, designation and phone are fields in the given table.

                Records/Rows/Tuples: A record, also known as a row or tuple, is a collection of multiple data values
                 stored in related fields that can be treated as a single unit. Each row represents a single data item in
                 a table.
                For example, 22, Aryan, New Market Lane, Accountant, 990845XXXX is one of the records of the table
                 given below:

                                                         Fields



                               Age      Name          Address         Designation        Phone
                                22     Aryan     New Market Lane      Accountant      990845XXXX
                   Table
                                50     Lucky     H.B. Road            Clerk           995525XXXX          Records
                                27     Rohit     New Fashion Street Cashier           986545XXXX




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