What is a relational database? Explain the advantages and disadvantages of the Relational database model in context to the cloud.

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RELATIONAL DATABASES

A relational database is a form of database that stores and allows access to data elements that are connected. Relational databases are based on the relational model, which is an easy-to-understand method of expressing data in tables. In a relational database, each row in the table is a record with a unique ID called the key. The columns of the table carry data attributes, and each record generally includes a value for each attribute, making it simple to construct links between data points.

In a relational database, each table, also known as a relation, includes one or more data categories in columns, also known as attributes. Each row, also known as a record or tuple, includes a unique instance of data, or key, for the columns' stated categories. Each table has a unique primary key that identifies the data in the table. The relationship between tables may then be defined using foreign keys, which are fields in one table that are linked to the primary key of another table.

A normal business order entry database, for example, might have a table that identifies a client, with columns for name, address, phone number, and so on. Another table would explain an order: the product, the client, the date, the sales price, and so on. A user of a relational database can then acquire a view of the database that is tailored to their requirements. A branch office manager, for example, would want a view or report on all clients who purchased items after a given date. A financial services manager in the same organization may acquire a report on accounts that needed to be paid using the same tables.

Advantages of Relational Database 

Accurate:

Data is stored just once, which eliminates data duplication.

Flexible: 

Complex queries are easy for users to carry out.

 Collaborative: 

Multiple users can access the same database.

Trusted: 

Relational database models are mature and well-understood. Secure: Data in tables within relational database management systems can be limited to allow access by only particular users.

Accuracy

A key feature of relational databases is that they’re strictly defined and well-organized, so data doesn’t get duplicated. Relational databases have accuracy because of their structure with no data duplication.

Ease of Use

Users can easily access/retrieve their required information within seconds without indulging in the complexity of the database. Structured Query Language (SQL) is used to execute complex queries.

Data Integrity

RDBMS databases are also widely used for data integrity as they provide consistency across all tables. The data integrity ensures the features like accuracy and ease of use.

Simplicity of Model

In contrast to other types of database models, the relational database model is much simpler. It does not require any complex queries because it has no query processing or structuring so simple SQL queries are enough to handle the data.

Disadvantages of Relational Database 

Maintenance Problem

The maintenance of the relational database becomes difficult over time due to the increase in the data. Developers and programmers have to spend a lot of time maintaining the database.

 Cost

The relational database system is costly to set up and maintain. The initial cost of the software alone can be quite pricey for smaller businesses, but it gets worse when you factor in hiring a professional technician who must also have expertise with that specific kind of program.

Physical Storage

A relational database is comprised of rows and columns, which requires a lot of physical memory because each operation performed depends on separate storage. The requirements of physical memory may increase along with the increase of data.

Lack of Scalability

While using the relational database over multiple servers, its structure changes and becomes difficult to handle, especially when the quantity of the data is large. Due to this, the data is not scalable on different physical storage servers. Ultimately, its performance is affected i.e. lack of availability of data and load time, etc. As the database becomes larger or more distributed with a greater number of servers, this will have negative effects like latency and availability issues affecting overall performance.

Complexity in Structure

Relational databases can only store data in tabular form which makes it difficult to represent complex relationships between objects. This is an issue because many applications require more than one table to store all the necessary data required by their application logic.

Decrease in performance over time

The relational database can become slower, not just because of its reliance on multiple tables. When there is a large number of tables and data in the system, it causes an increase in complexity. It can lead to slow response times over queries or even complete failure for them depending on how many people are logged into the server at a given time.

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