10 Reasons Developers Love NoSQL

By Adam Fowler

The popularity of NoSQL databases arises from the sheer number of developers who are excited about using them. Developers see NoSQL as an enabling and liberating technology. Unlike the traditional relational approach, NoSQL gives you a way to work with data that is closer to the application than the relational data model.

Developers adopt NoSQL technologies for many reasons, some of which are highlighted here:

No need to write SQL

Writing Structured Query Language (SQL) — and doing it well — is the bane of many enterprise developers’ existence. This pain is because writing very complex queries with multiple joins across related tables isn’t easy to do. Moreover, in light of regular database changes over time, maintaining complex query code is a job in and of itself.

Enterprise developers have invented a number of ways to avoid writing SQL. One of the most popular ways is through the use of the Object-Relational Mapping (ORM) library, Hibernate. Hibernate takes a configuration file and one or more objects and abstracts away the nasty SQL so that developers don’t have to use it. This comes at a cost in terms of performance, of course, and doesn’t solve all query use cases. Sometimes you have to fall back to SQL.

NoSQL databases provide their own query languages, which are tuned to the way the data is managed by the database and to the operations that developers most often perform. This approach provides a simpler query mechanism than nested SQL statements do.

Some NoSQL databases also provide an SQL interface to query NoSQL databases, in case developers can’t break the SQL habit!

Don’t have to spend months designing schema

Schema agnosticism in NoSQL databases allows you to load data quickly without having to create a relational schema over a period of months. You don’t have to analyze up front every single data item you need to store in NoSQL, as you do with an RDBMS.

Less data transform code (ETL)

A common problem with relational databases that comes from having an up-front schema design is that you have to force nonrelational data into rows and columns. This shredding mechanism, along with other code methods that preprocess information for storage and post-process it for retrieval is referred to as extract, transform, and load (ETL).

This code forces developers to take their nice shiny object and document models and write code to store every last element. Doing so is nasty and also leads to highly skilled developers writing poor performing and uninteresting plumbing code.

NoSQL databases allow you to keep the stored data structures much closer to their original form. Data flowing in between systems is typically in an XML format, whereas when it comes to web applications, data is formatted in a JSON document. Being able to natively store, manage, and search JSON is a huge benefit to application developers.

Easier to maintain code

All the code that you write must be maintained. By keeping database structures close to the application code’s data formats, you minimize the amount of code, which in turn minimizes the maintenance of code and regression testing that you need to do over time.

When data structures change on an RDBMS, you have to review all SQL code that may use the changed tables. In NoSQL, you simply add support for the new elements, or just ignore them! Much easier to maintain, thanks to the schema-agnostic nature of NoSQL databases.

Execute code close to the data for the best performance

An RDBMS provides stored procedures for executing code on a database server. This code is executed in one place. This useful approach is the basis of many analytical and complex data-management applications.

Many NoSQL databases allow this type of code to be distributed across all servers that store relevant data, which allows for greater parallelization of the workload. This approach is especially important for large ingestions of data that need processing and for complex aggregation analytics at query time.

User-defined functions (UDFs) and server-side scripting in a variety of NoSQL databases provide this distributed capability. UDFs are similar to Hadoop’s MapReduce capability, except UDFs can happen in real time rather than in batch mode and doesn’t require the same outlay in infrastructure that Hadoop plus a database would require.

Lots of open-source options

In many enterprise software areas, the choice of a solid open-source solution is lacking. Only one or two widespread options may exist. Availability of skills and local in-country support are even bigger problems.

However, there are a myriad of open-source NoSQL databases. Many of these have full-fledged commercial companies that offer support and have offices globally. So, if you do need support or more features, you can move to those versions eventually.

This reduces the cost of adopting NoSQL technology and allows you to “try before you buy.” This availability of open-source alternatives has caused commercial companies in the NoSQL space to offer free but well-featured versions of their software or to offer special startup licenses to small organizations.

Easy to scale

You don’t need to get a costly DBA to spend days refactoring SQL and creating materialized views in order to eek every inch of performance out of NoSQL systems.

Key-value stores can handle hundreds of thousands of operations per server. All types of NoSQL can scale horizontally across relatively cheap commodity servers. So, it’s much easier to scale your database cluster with NoSQL than with traditional relational databases.

In addition, because of their ability to scale, NoSQL databases also fit well into public and private clouds. NoSQL databases are designed to be flexible and expand and contract as the uses for your application change. This capability is often called elasticity.

Eventual consistency data model

Although mission-critical cases require ACID compliance, not every application needs to do so. Being able to relax consistency across very large clusters can be useful for some applications.

NoSQL databases allow you to relax these constraints or to mix and match strong consistency and weak consistency in the same database, for different record types.

Esoteric language support

Pretty much all databases support the main programming languages such as Java and C# .NET. Many databases support the likes of PHP, Python, and Ruby on Rails.

NoSQL has a flourishing set of language drivers for an even wider range of programming languages. If your organization has a domain-specific language, you may well find support for it in a NoSQL database.

JavaScript end-to-end

JavaScript use has exploded in recent years. It’s a convenient scripting language both on the web and, thanks to Node.js, on the server-side.

Many NoSQL databases now support full end-to-end JavaScript development. This means your organization can now use the same pool of programming language skills to craft web applications and middle tier data APIs and business logic, as well as handle back-end database triggers and MapReduce-based analytical processing next to the data.

As a result, in comparison to other database technologies, the total cost of ownership (TCO) of NoSQL is lower.