Database management is fundamental for office administration professionals who handle large volumes of data daily. Effective use of database management systems (DBMS) enables efficient storage, retrieval, and manipulation of information, which supports decision-making and operational activities. In the Kenyan office environment, from county government offices to financial institutions, mastering DBMS tools enhances data accuracy, security, and accessibility. This chapter introduces the core concepts of database management systems and guides the installation of relational database software tailored to office administration needs.

15.1 Concepts of database management systems

A database is an organised collection of related data stored so that it can be found, updated and reported on easily, for example all the staff records, customer details or stock items of an organisation. A database management system (DBMS) is the software used to create the database, store data in it, keep it accurate and secure, and retrieve it. Instead of separate files and spreadsheets kept by different people, a DBMS holds the data once, shares it among authorised users and controls who can see or change it.

Basic terms

• Field: one item of data about something, such as Surname or Phone number (a column).
• Record: all the fields about one person or thing (a row).
• Table: a set of records about one kind of thing, such as Employees.
• Primary key: a field whose value is unique for every record, such as an Employee number.
• Foreign key: a field in one table that holds the primary key of another table, linking them.

Advantages of using a DBMS

• Less duplication: data is stored once, so it is not typed and kept in several places.
• Consistency and accuracy: a change is made once and seen by everyone; validation rules reject wrong entries.
• Sharing: many users can work with the data at the same time.
• Security: user accounts and permissions control access.
• Fast retrieval and reporting: queries and reports answer questions in seconds.
• Backup and recovery: tools protect against data loss.

Other database models

• Network model: like the hierarchical model but a record can have several parents, allowing many-to-many links.
• Object-oriented model: stores data as objects, as used in some programming systems.
• NoSQL databases: store data as documents, key-value pairs or graphs, used for very large or fast-changing web data.

15.1.1 Relational database

A relational database stores data in tables (relations) made of rows (records) and columns (fields), and links the tables through common fields (keys). For example, a Customers table and an Orders table are linked by CustomerID: each order holds the ID of the customer who placed it, so customer details are stored once and not repeated in every order. Organising data into well-designed related tables to avoid repetition is called normalisation. Relational databases are widely used for business records.

15.1.2 Relational database management system (RDBMS)

An RDBMS is the software that creates and manages relational databases. It lets users define tables and relationships, enter and edit data, enforce rules (unique keys, required fields, valid links between tables), run queries, produce reports and control access. Most RDBMSs use SQL (Structured Query Language) to define and query data. Examples are Microsoft Access (desktop, suited to small offices), Microsoft SQL Server, MySQL, PostgreSQL and Oracle Database (server systems for large organisations and websites).

15.1.3 E. F. Codd: Proposed the relational model of data in 1970

Edgar F. Codd, a British computer scientist working at IBM, proposed the relational model of data in a 1970 paper, "A Relational Model of Data for Large Shared Data Banks". Before this, databases linked records through fixed paths (hierarchical and network models), so programs had to know how data was stored. Codd's model, based on mathematical set theory, represents all data as tables and lets users ask for data by its values rather than by its storage path. It led to SQL and to the relational database systems used today. In 1985 Codd also published twelve rules (numbered 0 to 12) for judging whether a system is truly relational, including that all data is held in tables and that data is independent of how it is physically stored.

15.1.4 Hierarchical DBMS

A hierarchical DBMS organises data in a tree structure: each record (child) has one parent, and a parent can have many children, like a family tree or an organisation chart (Organisation > Departments > Employees). It is fast for following the fixed paths it was designed for and was used in early large systems such as IBM's IMS. Its weaknesses are that it cannot easily represent many-to-many relationships (an employee working in two departments must be stored twice) and that new kinds of questions require reorganising the structure. For these reasons relational databases replaced it for most business uses, although hierarchical structures survive in some older systems and in file systems and XML documents.

Chapter Summary

This chapter explored the fundamental concepts of database management systems, focusing on relational databases and the relational database management system (RDBMS) model introduced by E. F. Codd in 1970. It also covered other database structures such as hierarchical DBMS. The process of installing a relational database was outlined to provide practical understanding. Key components that form the basic environment of a relational database were examined to highlight their roles. The chapter detailed the primary functions of an RDBMS, including data storage, retrieval, and manipulation. Practical steps for opening a new database using Microsoft Access were demonstrated. The various relational database objects such as tables, queries, relationships, and reports were explained along with their applications within the RDBMS framework. Finally, the chapter discussed the creation of forms and the printing of reports to complete the database management process.