two main early navigational data models were the hierarchical model and the CODASYL model (network model)
Advantages and Disadvantages of primary data are: Advantages 1. Data is basic 2. Unbiased information 3. Original data 4. Data from the primary market/ population 5. Data direct from the population. Disadvantages. 1. Large volume of data. 2. Huge volume of population. 3. Time consuming 4. Direct and personal intervention has to be there. 5. Raw data.
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1. files are can easily get damaged for e.g by water or fire and etc but a data base cant so easily get damaged you can find delete or edit files on the data base easily while if you hv a big file it is hard
Codes are uniqueCodes are short
The model's main function is to help us understand the complexities of the real-world environment. Within the database environment, a data model represents data structures and their characteristics, relations, constraints, and transformations. Good database design uses an appropriate data model as its foundation. Plus, a data model provides a blueprint of the data that is required for a functional system.
in which is a two dimensional array of data
Advantages of context data model include improved data organization and management, better understanding of relationships among data entities, and enhanced data retrieval efficiency. Disadvantages may include increased complexity of data modeling and potential challenges in defining and maintaining contextual relationships accurately.
Network data model is just like a normal database model. In network model the data is seen as related to each other by links. Or we can say the relation between the data is represented by links.
Hierarchical data model :Advantages- simplicity- data security- data integrity- efficiency- ease to add and delete recordDisadvantages- implement complexity- database management problem- lack of structural independence- programming complexity- implementation limitation- procedural access languageNetwork data model :Advantages- easy to access data- can handle more relationship types- data independence- data integrity- data independenceDisadvantages- system complexity- lack of structural independence- procedural access language
The flat-file model stores data in a single table or file without any relationships between tables. In contrast, the database model organizes data into multiple interrelated tables with defined relationships, providing more flexibility, security, and scalability. Databases also offer features like data integrity enforcement, concurrency control, and support for complex queries.
what are the advantages of a data projector
Entity-relationship model advantages and disadvantages AdvantagesDisadvantagesConceptual simplicityVisual representationEffective communicationIntegration with the relational database modelLimited constraint representationLimited relationship representationNo representation of data manipulationLoss of information
With a simplified rep, less of the model data is loaded into memory. Computer performance is improved.
what are the advantages and disadvantages of the biomedical model
Advantages of dynamic model
what are the 6 advantages of electrinic data processing
Entity-Relationship diagrams are useful for modelling data and the relationships between the data. They can be used when the constraints between data are relatively simple. They do not allow specification of interactions between the data or model how the data changes (there are no processes in Entity-Relationship). Entity-Relationship diagrams are most often used to model databases.