Session 1 RDBMS Concepts
Data management
Data management is the process of controlling the information generated during a research project. Any research will require some level of data management, and funding agencies are increasingly requiring scholars to plan and execute good data management practices.
File-based system: a system of analyzing and organizing data by files:
- It’s difficult to standardize file of data -> data file will be inconsistent.
- It’s hard to query: means it’s difficult to analyze a large amount of files.
- The relation among files is too week.
Databases are used to store data in an efficient and organized manner. A database allows quick and
easy management of data. For example, a company may maintain details of its employees in various
Database Management System: DBMS:
A database management system (DBMS) is system software for creating and managing databases. The DBMS provides users and programmers with a systematic way to create, retrieve, update and manage data.
Database Models
- Flat File Data Model: Database only contain one table or file: simple model.
- Hierarchical Model: a kind of TREE structure database.
- Network data model: wider than Hierarchical Model, Network data model provide an exception of relation between children and parents: children can be inside of many parents.
- Relational Data Model: All data stored in form of table with rows and columns, and tables related to others by common columns, not physical links.
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