Relational database stores and accesses relevant data points and is based on relational models, a perceptive and easy way to represent tables of data.
Each row in the table is a record with a unique ID called a key in a relational database. The columns in the table contain attributes of the data. Each record generally has a value for each attribute, making it easy to establish the relationships between the data points.
Structure of relational databases
The relational model means that the logical data structures such as the data tables, views, and indexes are separate from the physical storage structures. This separation means that database administrators can manage the physical storage of data without affecting access to that data as a logical structure.
Logical operations allow an application to specify the content it needs, while physical operations determine how that data should be accessed and then perform the task. To ensure that data is always accurate and accessible, relational databases follow certain integrity rules.
Benefits of relational databases
Organizations of all types and sizes use the simple but powerful relational model for a wide variety of information needs. Relational databases track inventory, process commercial transactions, manage important customer information, and do much more.
A relational database can be considered for any information need where data points are related to each other and must be managed in a secure, consistent, and rule-based manner. The best relational database software has the following features:
Consistent data
The relational model is best for maintaining data consistency across applications and copies of the database. For example, when a customer deposits money at an ATM and then looks at the account balance on a mobile phone, the customer expects that deposit to be immediately reflected in an updated account balance. Relational databases ensure consistency, making sure that the same data is present at all times in multiple database instances.
Compromise and atomicity
Consider an inventory database that tracks the three components that are always used together. When one part of the inventory is removed, the other two must also be removed. If one of the three parts is not available, none of the parts must be removed; all three parts must be available before the database is compromised.
A relational database will not commit for one party until it knows that it can commit for all three. This multifaceted capacity for compromise is called atomicity. Atomicity is the key to maintaining the accuracy of the data in the database and ensuring that it complies with company rules, regulations, and policies.
Stored procedures and relational databases
Access to data involves many repetitive actions. For example, a simple query to retrieve information from table of data might require repeated initiations to produce the desired result. Fortunately, relational databases allow stored procedures, which are blocks of code that can be accessed with a simple application call.
Database locking and concurrency
Conflicts in a database can arise when multiple users or applications try to change the same data simultaneously. Blocking and concurrency techniques reduce the possibility of conflicts while maintaining data integrity.
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