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Maria M.
Maria M.

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SQL vs NoSQL: Choosing the Right database for Your Project

As a software engineer with years of experience in the market, I've had the opportunity to work with a wide variety of databases, both SQL and NoSQL. Choosing between these two categories of databases is very important and can have a significant impact on the performance, scalability, and ease of development of your application. In this post, we will explore the pros and cons of SQL and NoSQL, providing a clear guide to help you make an informed decision.

SQL: Structure and Reliability

Pros:

  • Defined Structure: SQL databases, like MySQL or PostgreSQL, use a predefined schema that helps maintain the structure of the data. This is ideal for data that does not change frequently and requires consistent organization.
  • Data Integrity: Thanks to ACID transactions (Atomicity, Consistency, Isolation, Durability), SQL databases ensure high data integrity.
  • Uniform Language: SQL is a standardized language that allows for efficient complex queries, ideal for detailed analysis and reports.

Cons:

  • Vertical Scalability: SQL databases often require vertical scalability (upgrading existing server hardware), which can be costly and has its limits.
  • Limited Flexibility: Changes in the schema can be difficult and laborious, which can be challenging in agile environments with changing requirements.

NoSQL: Flexibility and Scalability

Pros:

  • Horizontal Scalability: NoSQL databases, like MongoDB or Cassandra, are designed to scale horizontally, using server clusters, which makes it easier to handle large volumes of data and traffic.
  • Dynamic Schemas: They allow greater flexibility as data can be stored without a defined schema. This is ideal for data that changes or evolves frequently.
  • Diversity of Types: NoSQL includes various types such as document-based, key-value, wide-column, and graph databases, each optimized for different types of queries and access patterns.

Cons:

  • Eventual Consistency: Some NoSQL databases offer eventual consistency instead of ACID transactions, which may not be suitable for applications that require high data integrity.
  • Complexity in Queries: Performing complex queries can be more challenging in NoSQL due to the lack of a standardized query language like SQL.

Which to Choose?

The decision between SQL and NoSQL largely depends on the specific needs of your project:

  • Choose SQL if... your data requires a rigorous structure, data integrity, and complex querying capabilities are a priority.
  • Choose NoSQL if... you are working with large volumes of data or data that changes frequently, and need scalability and flexibility.

The choice between SQL and NoSQL is not a one-size-fits-all decision. Each project has its unique requirements and challenges. As software engineers, our job is to understand the characteristics and limitations of each type of database to make the best possible choice that supports the needs of our projects and clients.

Top comments (5)

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rickdelpo1 profile image
Rick Delpo

hey Thanks @marmariadev , check out this detailed article about why I recently chose nosql using a json data source instead of sql. I use this approach mainly for small use cases where we don't need any relationships in the data, for example creating a quick dashboard
dev.to/rickdelpo1/to-sql-or-to-nos...

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marmariadev profile image
Maria M.

Hi Rick,

Thanks for sharing your article and experience with using NoSQL and a JSON data source. It's always valuable to see real-world examples, especially your rationale for choosing NoSQL in scenarios where data relationships are not a primary concern, like in creating quick dashboards. Your approach highlights the practical side of NoSQL's flexibility and ease of use for certain use cases. I'll definitely check out your article for more insights!

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rickdelpo1 profile image
Rick Delpo

thanks for the positive feedback it is appreciated. I was stuck in Java and SQL on the job for 20 years and since my retirement 5 years ago I explored Javascript and NoSQL. Its been fun learning and writing about it.

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marmariadev profile image
Maria M.

Hi Rick,

It's really interesting to hear about your switch from Java and SQL to JavaScript and NoSQL after retiring. Your experience shows how tech keeps changing and how important it is to keep learning. Using NoSQL for things like quick dashboards, where you don't need complex data links, really shows how useful and flexible NoSQL can be. Your journey and articles are helpful for all of us, giving insights into how these technologies are used in real life. Keep sharing your experiences and thoughts!

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rickdelpo1 profile image
Rick Delpo

So everything boils down to the use case when choosing sql vs nosql. Sometimes u just don't need the complexity of full blown sql in an external database so a json file saved in AWS S3 will do in these circumstances. In my travels as a programmer I had the unique opportunity to be an IT person in a Marketing department, a big fish in a small pond. In Marketing we are always developing reports based on subsets of a larger data store (the source of truth managed by IT dept). So many times I would be asked to develop a solution for a small report and I then went on my ad hoc adventure. The boss never cared how it was done as long as it worked. By 2016 Javascript was becoming very mature and thanks to the fetch API we were all able to ditch JQuery Ajax in favor of a wider range of creative frontend solutions. Also I think that by this time Hadoop was dead. Since I was stuck in SQL for so long I only occassionally had an opportunity to explore NoSQL solutions. But then I became hooked because our subsets of data were always only maybe 1-5 columns of the larger data set, so a quick dashboard meant I could frontend some js via Fetch api to my json data and return the report in Javascript. No longer did I need Java, JDBC or servlets to accomplish this. Bottom line, what is the use case? does it only involve some small amounts of data from a larger source? Ask for a csv from your central IT department and just grab the fields needed for the dashboard and convert them to json and in my case I stored it in S3. Here is an example of a stacked bar chart in plain js at

dev.to/rickdelpo1/how-to-populate-...

happy coding!