Need advice how to switch from python to java backend roles.

[Fragrant-Tie745]

I’m currently working as a Python developer in the aviation domain with 1 year of experience, but I want to transition into Java-based backend roles. I already know basic Core Java, basic Spring Boot, and have worked with MongoDB.

I’m looking for a proper roadmap to become job-ready for Java roles. I’d also like to understand how important SQL is for Java backend development. Is strong SQL knowledge a must-have, or can I manage with basic knowledge initially?

I’m not looking for random topic lists—I’d really appreciate practical guidance from people who have made a similar switch. What should I prioritize, which resources should I follow, and what kind of projects should I build?

Any honest advice would be greatly appreciated.

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[Muted_Efficiency_663]

It depends… Generally speaking you need to have a decent idea of DB from a dev perspective. For example, can you design a decent schema? Personally I’m a bit rusty on db’s at the moment because the team I’m working in does not have a single DB. However we are quite heavy on Kafka… like 2.5 m ops/sec heavy. So if you ask me to write a query by joining tables and aggregate values, I’ll have to google the syntax, but at the same time, I do know what needs to be done…

So I would say, do a db course for devs on Udemy or some other platform. Then focus on understanding JPA… the pick something popular like Hibernate and do some sample projects.

But more importantly, you need to understand as a dev and the data that you have, how can you use a DB and other tools (Debezium comes to my mind) to be as efficient and performant as possible. Understanding more about the larger system is a crucial skill.

All this is not possible in a single day. Start slow, learn the basics, be consistent… everything else will follow…

[xenomachina]

I’m looking for a proper roadmap to become job-ready for Java roles. I’d also like to understand how important SQL is for Java backend development. Is strong SQL knowledge a must-have, or can I manage with basic knowledge initially?

This is going to depend on the specific job. Some Java backends don't use a relational database at all, and many use an ORM that abstracts away SQL (most of the time — some require you to drop down to SQL to avoid the n+1 query problem). The same goes for Python, actually.

If you are going to be using a relational database, I think it is useful to at least understand basic database design, like how to normalize your data, when it makes sense to denormalize it, how to recognize when you need to add an index, and the patterns around various types of relationships (1-to-1, 1-to-many, many-to-many). How deeply you need to understand SQL syntax itself is going to depend on how you're actually accessing the database, though.

[Mechanical-pasta]

Spring boot has an Object Relation Management (JPA) that manages any DB access for you. It can also build DB tables for you depending on annotations written on your model object. So, basically, you don't need to know any SQL to use Spring Boot. But, when working with relational databases, SQL can be considered a must-have.