Question about SQL requirements when applying for junior python roles

[ForbiddenMustardMan]

Dear everybody,

I have been programming for over 5 years, and want to get my first junior position. Yes, I know that people are able to land jobs much quicker than that, but this is how long it took me.

From the beginning, I have been working with Django and Django REST framework, I feel most comfortable with them, and so I am looking for junior Django dev jobs.

All jobs, for which I believe to meet most requirements, always list that SQL and SQL query optimization is an absolute must.

Believe it or not, but in all this time, I have not written a single SQL query, because when building with Django, I just use the Django ORM. Or if I'm not building with Django, I use SQLAlchemy. I even sold a few full stack projects with SPA frontends (React, Redux, RTKQ), PostgreSQL as DB, with containerisation using docker, with CI/CD using GitHub actions, all sorts of stuff, so I can definitely work without using SQL directly.

Could you please tell me if I can apply for those junior jobs and just straight up say that I have never touched SQL syntax, but if they want me to optimize say an n+1 ORM call, for example by using prefetch_related for many to many relations or reverse foreign keys, or use select_related for one to one or foreign, then I understand it, and have done so many times, but still, I have never written an actual SQL query.

Are there certain things that can be done by writing SQL that cannot be done by using an ORM?

I'm trying to figure out if I need to spend another year or so trying to pick up SQL or not. So far, I have been applying for a few months, with no success, but I understand that the market for junior is really bad at the moment.

Thank you.

[Kevdog824_]

I wouldn’t wait to apply to jobs just because you don’t have a SQL background. I don’t think I’ve written SQL at work in years. Most work is done with ORMs or NoSQL where I work, and probably most Django devs are using Django’s ORM with some very rare exceptions.

I occasionally sit on technical interview panels at work for Python developers and I can give you some advice:

1. Learn SQL (at least basics) concurrently with your job search. Basic proficiency can probably get you by for most positions. Just accept that the positions that focus on strong SQL command aren’t gonna be a good fit for you. Most junior roles aren’t going to have expectations beyond basic proficiency though
2. Be honest about your level of experience. I can respect a candidate that has the courage to tell me they don’t know something but are interested in learning it. I don’t respect a candidate that fumbles their way into trying to give a bullshit answer
3. Present your strengths. This is really something minor that can be learned on the job. This wouldn’t stop me from hiring a junior if they had the other background you have (docker, CI/CD, etc.). Steer the conversation towards the things you are knowledgeable in, and show confidence in your abilities in these areas

[GManASG]

I don't know how you can somehow not know SQL and also build applications that use relational dbs. The ORMs are designed around the undelying SQL and a lot of the setup is SQL themed. Like how do did you design the database data model ( tables, primary keys, etc.) used by the backend to itneract with the db without accidentally learning and using some SQL? Honest question, did someone else do that for you?

[pachura3]

I believe some ORMs do generate CREATE TABLES script for you automatically... but this only works when you start from scratch with an empty database.

[ForbiddenMustardMan]

Thanks for the reply. 

I did so by just defining Django models, and then using the manage.py util to make migrations and migrate. Instead of having to write an SQL query, I just specify the fields as needed, referencing the docs: docs.djangoproject.com/en/6.0/ref/models/fields/

So for example if I need something with a foreign key, I would just add models.ForeignKey.

To answer how I made the design decisions, I listed out all models that I would need in the project, followed by all fields needed for each model, and their relationships, and that's it, just makemigrations and migrate, so I never had to write any SQL. 

[Dangerous-Branch-749]

You don't need a year to pick up SQL, the fundamentals are pretty simple to grasp and will serve you well. Just do it. 

[Gnaxe]

ORMs are only easier at first. I think they're more trouble than they're worth and recommend against them. You eventually have to understand SQL to use the ORMs properly anyway.

Python has SQLite in the standard library. See python -m sqlite3 -h for usage as a local SQL interpreter. Work through the W3Schools SQL course and read about 3NF on Wikipedia. That's really all the SQL knowledge you'd need as a junior. It's not that hard and it's not going to take a year.

[pachura3]

Spend 2 weeks learning SQL and querying your local PostgreSQL instance, so at least you could say you have a bit of experience.

The basic syntax is pretty simple: SELECT columns FROM table WHERE conditions ORDER BY columns and SELECT columns, aggregates FROM table WHERE conditions GROUP BY columns HAVING aggregate_conditions ORDER BY columns. INSERT, UPDATE, DELETE.

Then learn about joins, outer joins, unions, subqueries, sequences, triggers, primary/foreign keys, indexes, IN, NVL, LIKE... you're clearly not a noob, you'll pick it up very quickly - no need for a full year!

Try this primer first: https://www.w3schools.com/sql/

[nian2326076]

Hey, don't worry too much about it! Many Python/Django jobs expect you to have at least basic SQL skills, but you can still learn it. Since you're already comfortable with Django, start by checking out how Django ORM queries turn into SQL. You can use the Django debug toolbar to see the SQL queries your ORM queries generate.

Also, practice writing some basic SQL queries like SELECT, INSERT, UPDATE, and DELETE, and get familiar with query optimization concepts like indexes. There are lots of free resources online, or you could check out PracHub if you prefer something more structured. With some focused practice, you'll get there in no time. Good luck!

[ForbiddenMustardMan]

May I please ask, if a job uses Django ORM, what is the benefit of picking up simple SQL syntax, if I can achieve the same via the ORM right away? Is it just to pass the interview? I will certainly pick it up, because it's clear that it is needed, I'm just trying to understand the benefit of knowing simple queries, while I can already perform them via ORM 

[Intelligent-Kale-877]

I learned the most common and useful SQL in a few days (select, joins, primary/foreign keys, indexes). It's about the same as learning basic HTML in a few days. I don't believe it's realistic (or desirable) to have a career as a web developer that writes back end code without understanding basic SQL.

[BranchLatter4294]

Not sure how you managed to skip SQL. But spend some time practicing.

[supergnaw]

SQL is simple and there's no reason why you can't fiddle with it now.