r/learnSQL

I’ve been practicing things like joins, window functions, etc., but I feel like just solving questions isn’t enough.

What made the biggest difference for you:
- Timed practice?
- Explaining your approach out loud?
- Reviewing mistakes?

Trying to figure out what actually works vs just grinding questions.

Hi and thank you in advance.

I currently work in a bank and am quite into computers. Given the rise in ai, banking is very much incorporating it. There is also a huge shift towards data analytics. Due to this, and to further advance my career, I’m wanting to learn sql. I just wanted to ask a few questions. I appreciate anyone taking time to read and answer.

1. the most obvious, where would you recommend to start? Looking online is a bit overwhelming with the options.

2. I have a MacBook, running iOS, and a pc, running windows. If there a significant different between the 2? Should I stick to windows based systems or would it not be an issue to use both ?

3. is there anything else I should consider learning alongside sql, that would be helpful?

Thanks again!

Fresher here, in the learning process. I haven't stepped into the real data world but I would love to know how to grasp business questions and relate them to sql to fetch data?

Do clients/managers ask - Find average salary per employee or how do they ask?

Because if they are vague like *find average salary* then it could be the average salary of the whole table ?

How do you map business questions to sql? Any tricks?

Learning tools like sql , excel , python , power bi , tabulea, etc for data analytics is not sufficient i guess. Having buisness oriented knowledge is must .

Can anyone tell me what exactly to do ??

Wanting to attempt a project looking into app costs on the apple app store & google play and calculating average/user download at different price points/different app genres etc as a way to start learning SQL and get more confident with python. Would this be a good project to do to learn SQL or is it more of a python-only project?

Basically,I wasted 2 years in competitive exams..now I am fed up..I want to learn skills..please help

[removed]

CREATE TABLE Library (

book_id INT PRIMARY KEY,

book_name VARCHAR(50),

author VARCHAR(60),

price INT NOT NULL

);

Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'Library ( book_id INT PRIMARY KEY, book_name VARCHAR(50), author VAR' at line 1

What do you think is wrong with the code?

I m using mysql.

Hey everyone,

I’m currently a 3rd year CSE student and I’ve realized that SQL is pretty important for placements, especially for interviews and coding rounds. The problem is I haven’t really learned it properly yet — just some basic queries in college.

I want to start from scratch and get to a level where I can solve interview-type questions confidently.

Can you guys suggest:

Good websites/platforms to learn SQL from basics Places where I can practice questions (easy → advanced) Any roadmap or approach that worked for you

I don’t mind putting in the time, just want to do it the right way without wasting effort on random resources.

Thanks in advance! 🙌

From MIS to Data analyst/scientist transition, I tried sql and it's been breaking my head. The logic is always turning wrong. each time I code, I have to take help from chatgpt.Its been a month already and I'm stuck with joins exists recursive cte etc etc

I was planning to transition to data analyst/scientist and now I'm on the verge of giving up.

How do i develop the thinking behind the code part ? Any resource or anyone can share how they go about their coding work?

I have two tables, Table1 has a list of medication orders, and Table2 has a list of transactions related to the orders in Table1 (one-to-many relationship).

Is there a way to use a single SQL query to select only the most-recent transaction row from the transaction table for each row in the medication orders table?

Table2 has columns: transaction_id, order_id (foreign key to Table1), t_date, t_time, etc. to represent transactions related to the medication orders in Table1.

Hopefully that's clear. I can't wrap my head around using max() in this way.

Which topics one should learn for data analytics ???

Anyone out there know about sololearn courses ? I want to be related to Data analytics

If yes , plzz tell was it worth it??

Also mention which courses you did on sololearn platform .

Get products that are more expensive than any 'Furniture' category product using Subquery.

All the AI platforms are confused in finding the exact meaning of this question.

Should ÀNY or ALL be used?

I'm have a dataset of contracts with start and end date that I fill using a SQL query. I know it is possible to filter to keep only the active contracts between two dates, (like for a quarterly report) in the SQL query directly.

My question is, using Superset, is it possible to filter the dataset using another dataset that holds the start and end dates of the quarters. Like by clicking on a quarter, it filters the contract dataset to only contracts active during this quarter?

Thank you for any help you can bring me!

Hi everyone,

I recently worked on an HR Attrition Analysis project using SQL with a real dataset.

I explored:

- Attrition rate

- Department-wise analysis

- Salary vs attrition patterns

One key insight:

Low salary roles had significantly higher attrition.

I’m still learning, so I’d really appreciate feedback:

- Is my analysis approach correct?

- Anything I could improve?