A database management system
is a software package for creating and managing databases. There are many different types of database systems depending on how they manage the structure of the database.
Two types of database structure
Databases typically have one of two basic forms:
single-file or flat-file database
- Multi-file relational or structured
database A flat file database stores data in
a plain text file
, and each line of text typically contains a record. Delimiters such as commas or tabs separate fields. A flat file database uses a simple structure and, unlike a relational database, cannot contain multiple tables and relationships.
A relational database contains several data tables with rows and columns that relate to each other through special key fields. These databases are more flexible than flat file structures and provide functionality for reading, creating, updating, and deleting data. Relational databases use Structured Query Language (SQL), a standard user application that provides a simple programming interface for database interaction.
There
are four types of relationships in relational database design:
one-to-one – where one table record relates to another record in another table one to many – where one table record relates to several records in another many-to-one table – where more than one table record relates to another
- many-to-many table record
- – where several records relate to
- more than
- one record in another table
These relationships form functional dependencies within the database. Some common examples of relational databases include MySQL, Microsoft SQL Server, Oracle, etc.
Four
types of database management systems
A relational database management system is one of four common types of systems that you can use to manage business data. The other three include:
hierarchical database systems
- network database systems
- object-oriented
- database systems
- hierarchical
A
database model
resembles a tree structure, similar to a folder architecture in your computer system. The relationships between the records are predefined in a one-to-one manner, between the ‘parent and child’ nodes. They require the user to pass a hierarchy to access the necessary data. Due to limitations, such databases may be limited to specific uses.
Network database models also have a hierarchical structure. However, instead of using a single-parent tree hierarchy, this model supports many or many relationships, because child tables can have more than one parent.
Finally, in object-oriented databases, information is represented as objects, with different types of possible relationships between two or more objects. Such databases use an object-oriented programming language for development.
NoSQL or
non-relational databases
A popular alternative to relational databases, NoSQL databases take a variety of forms and allow you to store and manipulate large amounts of unstructured and semi-structured data. Examples include key-value stores, document stores, and graph databases.
Which database is right for you?
Companies with simple database requirements often use standard office tools, such as spreadsheets. However, if you use large amounts of data or have complex business needs, you may need to consider more capable database systems that offer better functionality. Find tips to help you decide which database is best for your business.
See also 5 reasons why your company needs a good database.
