Relational databases are the standard when creating industrial standard efficient and scalable databases.
They are based on a structure of tables which are logically connected to each other and can be queried in complex way to extract relevant and meaningful information. The querying of a relational database is done using a high level language called SQL which stands for structured query language. SQL is very easy to understand and unlike traditional programming languages does not rely on arcane syntax, rather structured query language uses English like meaningful syntax in its operations.
As opposed to flat file databases this logical organization of data across tables in the form of columns greatly simplifies the organization and retrieval of highly complex data.
As the business needs of the client rises so will the size and complexity of data, on of the biggest advantages of relational databases is the scalability associated with them, so as the company grows expanding the database will not be a problem and making sense of the data and extracting meaningful information from it will only get slightly harder.
Relational databases come with a plethora of security options and views can be enforced to ensure that unauthorized access to the sensitive information in the database is not allowed.
Relational databases also avoid redundancy of information and such databases can be highly optimized by methods such as normalization and good database design to ensure lighting fast data storage and access.
There are relational databases catering to all consumer segments, for example the client can choose to go the open source way and use MySQL database for its operations or use Enterprise grade database software such as Oracle or IBM DB2 for its operations.
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