SQL and NoSQL are different types of database languages, they have their pros and their cons, but why is better to use one or the other? Is there any performance difference between them?
Contents
Languages or Databases?
First of all, let’s demystify a thing, SQL is a language, NoSQL is a group of languages that are used in non-relational databases, but they are not exactly the same.
We cannot talk about language performance, we can talk about the performance of the Databases, for instance, we can compare Redis (A NoSQL type of database) and OracleDB (A SQL type of database), which of them is faster? Which of them is better?
Faster for what?
When we talk about performance, therefore we have to talk about the different types of functions we have in a Database, to make a long story short, the most important things we do in a Database is store data and retrieve information from it, therefore, these two are the key values we are gonna examine.
Can we compare the performance of two SQL or two NoSQL databases?
Obviously, yes. For instance, OracleDB retrieves information and store data more efficiently and more quickly than MySQL, even though they are from the same company. There are databases designed specifically for Big Data, like Teradata that has its own appliance, therefore being developed more effectively for this task than typical databases.
On the other hand, Redis might be the fastest database of them all, it is designed for this purpose, and the database is stored in memory. MongoDB is designed for storing not relational data, but it doesn’t work in memory, therefore, is not as fast as Redis.
Using the correct Database
Depending on your needs (And your economic possibilities), you may use one database or another database.
For example, your server will most certainly run out of memory trying to load on Redis Big Data, so if you have very big large datasets, you should probably need to store them in another Database.
Continuing with NoSQL databases, Redis doesn’t have On-disk storage by default, MongoDB yes, Redis allow key-value entries only, MongoDB stores BSON ( Binary JSON) types of values with a maximum of 16MB, and allows you to search them by multiple keys, Redis will only let you search by the key.
And again, going to relational databases, SQL Server has a less complex syntax than OracleDB, SQL Server let you INSERT with a SELECT statement and OracleDB does not. Job Schedulers and Triggers are better handled by OracleDB optimizing their performance, SQL Server does not optimize it. Also, OracleDB executes queries in parallel while SQL Server does it sequentially (This makes OracleDB have better performance than SQL Server).
So why the confusion?
Actually, the confusion comes when you try to compare databases optimized to be fast versus databases optimized to Store Data.
Maybe the fastest database of them all is Cassandra, but it will not get you there if you try to store in it very large datasets.
On the SQL part, maybe the fastest would be RediSQL, but again, it certainly won’t get you there if you have very big datasets as it is an In-Memory database and it doesn’t have a management UI.
Conclusion
In conclusion, we could say you should really inform yourself about the benefits and the weakness of a database engine before implementing it, whether it is a SQL or a NoSQL database. Although NoSQL solutions tend to be faster, they probably won’t be suitable for your needs.
If you want to know more about the difference between SQL and NoSQL I recommend you the next post.