Database

A database stores data in a structured way and allows for operations to be performed on that data. Databases are managed by a database management system which will provide extend functionality including the management of the security of the data.

Human resource management systems will typically use a relational database to hold its data. This type of database allows for relationship such as one to one, one to many and many to many. An example of one of these relationships is employees to roles; over time one employee can hold many roles (as they are promoted) matching the structure of a one (employee) to many (roles).

A relational database is made up of data tables which themselves contain multiple columns. A data table is populated with rows of data. Unlike in Excel each column in a database table can only hold the type of data it has been assigned. Within the table one or a collection of columns within the table can be used to uniquely identify a single row of data in the table, this is known as a key. One key will be used as a primary key within the table which prevents duplicate records from being entered. To form a relationship between two tables one (or both) table will have a column that holds the primary key of the other table. The data in the tables can then be linked together by matching those values, forming a (virtual) larger table.

Software as a service provider typically host all client data in a single database and use technologies built in database management systems to keep the data separate. In this type of system, it is typical that the database has a fixed structure, so it is not possible for a user to add additional columns or tables to the system since these would be shared with all users of the system. Vendors may offer large scale client’s private versions of their systems which may allow for bespoke customisation to be made.

Self-hosted human resource management systems typically offer more flexibility in their database structure. These systems typically include tools which allow for designing of custom screens or altering existing ones; these tools are in the background adding and updating the database tables and columns as required. Screen design tools have been a standard feature of human resource management systems for approximately twenty years.