SQL vs NoSQL: The Main Differences

However, it is more efficient to scale out and use a cluster of on-demand servers. NoSQL the actual program appears to be a relational database implemented in awk using flat files on the backend. While most NoSQL databases abandon the concept of managing data relations, these databases when to use NoSQL vs SQL embrace it even more than those so-called relational databases. For decades, when people were talking about databases, they meant relational databases. And when people were talking about relational databases, they meant those you control with Edgar F. Codd’s Structured Query Language.

Using ACID, each transaction — when executed alone, in a consistent database state — will either complete, producing correct results, or terminate, with no effect. In either case, the resulting condition of the database always will be a consistent state. The term NoSQL originally could be taken at its word — that is, SQL was not used as the API to access data. However, the ubiquity and usefulness of SQL caused many NoSQL databases to add support for SQL. Today it is commonly accepted that NoSQL stands for « Not Only SQL. »

Continue exploring your data

If you need to find the release date for the Radiohead album, OK Computer, the response is lightning fast. The query provides results much quicker as it does not need to retrieve information from multiple tables (as in relational databases), but rather from a single entry. A NoSQL datastore is non-relational, distributed, flexible, and scalable. Also called document stores, these databases store semi-structured data and descriptions of that data in document format.

what is NoSQL

The native data type it applies is the Standard ECMA-404, using the Standard JSON Data Interchange Syntax. JSON outperforms any other technique for storing JSON objects in Redis, such as using Lua for manipulating JSON or MessagePack objects. NoSQL databases are also the preferred choice of developers, as they naturally lend themselves to an agile development paradigm by rapidly adapting to changing requirements. Moreover, NoSQL databases can take full advantage of the cloud to deliver zero downtime.


Relational databases are unable to meet these new requirements, and enterprises are therefore turning to NoSQL database technology. SQL database schema organizes data in relational, tabular ways, using tables with columns or attributes and rows of records. Because SQL works with such a strictly predefined schema, it requires organizing and structuring data before starting with the SQL database.

Storing this resume would require the application to insert six rows into three tables, as illustrated in Figure 3. While NoSQL has quickly been adopted, it has smaller user communities and, therefore, less support. NoSQL users do benefit from open-source systems, as opposed to the many SQL languages that are proprietary. Many begin with NoSQL by applying it in new cloud applications and starting from the ground up. This approach avoids the pain of application rewrites and data migrations.

When to use: SQL vs. NoSQL

The data inside the document is semi-structured to provide more flexibility when querying. Unlike basic key-value stores, the user does not need to retrieve the entire record, only the relevant part of the document. Redis is an extremely performant key-value database that stores small keys and strings entirely in RAM, which is much faster to read and write to than even the quickest SSDs.

what is NoSQL

While in some cases this may mean that SQL databases are limited by the resources available on the server, cloud-based storage and other technologies can provide more scalability with SQL. Because of their architecture differences, NoSQL databases differ in their support for reading, writing, and distributing data. NoSQL platforms like Cassandra support writes and reads on every node in a cluster and can replicate or synchronize data between many data centers and cloud providers. Coherent integration and interoperability of mixed workloads and multiple data models. Since the document database can inspect the document contents, the database can perform some additional retrieval processing.

Graph databases

If you determine that a strict schema is limiting your data flow and forcing you to add new fields and tables, a NoSQL database can be an effective solution. You can increase productivity by using a NoSQL database that better matches your application’s needs, scales out quicker, or has excellent throughput. Inconsistencies on reads are eventually resolved, but the lack of consistency on writes is a serious issue. This problem is often solved by limiting all database interactions within a single application and integrating it with other applications using web services.

what is NoSQL

In this chapter, you will learn in details about NoSQL and its characteristic features. Key-value databases, sometimes referred to as key-value stores, use the simplest data model – the pairing of a key and a value. Relational databases focus on consistency as the more important feature to maintain.

Create a cluster and a database

Some say the term “NoSQL” stands for “non SQL” while others say it stands for “not only SQL.” Either way, most agree that NoSQL databases are databases that store data in a format other than relational tables. SQL is a standard language for storing, manipulating, and retrieving data in relational database systems. Now, put the « Not Only » in front of the last sentence and you will get a definition of what means « NoSQL ». MongoDB, for example, uses a document model, which can be thought of as a row in a RDBMS.

  • When choosing a database for a specific application, it is important to weigh the benefits and drawbacks carefully to determine the best fit.
  • Wide-column stores use the table and row concept, but columns can be dynamic from row to row within a table.
  • The term ‘NoSQL’ refers to nonrelational types of databases, and these databases store data in a format that’s different from relational tables.
  • With the primary/secondary approach, most notably used by MongoDB, a replica set is created that contains one primary replica node and multiple secondary copies.
  • It uses a structured schema, and data is organized into tables with rows and columns.
  • Couchbase Server supports both key-value and document approaches.
  • NoSQL databases use JSON (JavaScript Object Notation), XML, YAML, or binary schema, facilitating unstructured data.

They enable developers to create and update programs without needing to reference master schema. Use of document databases has increased along with the use of JavaScript and the JavaScript Object Notation (JSON), a data interchange format that has gained wide currency among web application developers. Document databases are used for content management and mobile application data handling, such as blogging platforms, web analytics and e-commerce applications. Couchbase Server, CouchDB, MarkLogic and MongoDB are examples of document databases.

Key-Value Databases

NoSQL databases provide a viable solution by focusing on performance and availability while also sacrificing some of the consistency usually identified with relational databases. NoSQL originally referring https://www.globalcloudteam.com/ to non SQL or non relational is a database that provides a mechanism for storage and retrieval of data. This data is modeled in means other than the tabular relations used in relational databases.

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