SQL Study Plan for the Last 90 Days of the Year

The last three months of the year are the perfect time to focus on yourself and build skills that will pay off in the new year. With the right plan, you can go from SQL basics to job-ready queries by December 31. This 90-day study path shows you exactly what to learn — and when — using LearnSQL.com courses.

The final months of the year are a natural moment to reset and prepare for what’s ahead. As projects wrap up and holiday plans take shape, it’s also a perfect time to invest in yourself and focus on building skills that will pay off in the new year.

This path is for beginners who want to build a solid foundation in SQL and be ready to use it in job interviews or real projects at the start of next year. Whether you’re planning to move into data analysis, strengthen your current role with SQL, or simply add an in-demand skill to your resume, this plan gives you the structure to get there.

In just 90 days, you can move from SQL basics to confidently writing queries that would impress in a job interview. By the time January rolls around, you won’t just be setting resolutions — you’ll already have a new, marketable skill on your resume.

In this article, we’ll give you a simple 3-month study plan based on LearnSQL.com courses. You’ll know exactly what to learn in October, November, and December so that by the new year, you’ll be ready to step into job interviews with confidence.

October: Learn the Foundations

October is all about getting comfortable with SQL queries. By the end of the month, you should be able to read data from one or more tables, filter it, aggregate it, and even write subqueries. These are the essential building blocks for any SQL interview.

🚀 Main Course: SQL Basics

Spend most of October on this course. It walks you through the fundamentals step by step, from simple SELECTs to joins and subqueries.

What you’ll cover:

• Selecting and filtering data (SELECT, WHERE, ORDER BY, LIMIT)
• Working with NULLs and logical operators
• Combining data with JOINs (INNER, LEFT, RIGHT, FULL)
• Aggregations with COUNT, SUM, AVG, MIN, MAX
• GROUP BY and HAVING for grouped reports
• Subqueries in WHERE, FROM, and SELECT
• Set operations (UNION, INTERSECT, EXCEPT)
  

Suggested pacing:

• Week 1: Introduction, SELECT, filtering, NULL handling, basic JOINs
• Week 2: Aggregations, grouping, HAVING
• Week 3: More on JOINs, subqueries
• Week 4: Set operations, plus final course review
  

By the end of the course, you’ll be able to confidently answer interview-style questions like:
 “Find all customers who placed more orders than the average.”

🎯 Quick Add-On: How to INSERT, UPDATE, and DELETE Data in SQL

This short course can be done in 3–4 days alongside your main study. It covers how to add, modify, and remove data:

• INSERT single and multiple rows
• UPDATE values (simple and conditional updates)
• DELETE rows safely with conditions
• Using INSERT … SELECT to copy data between tables

It’s straightforward but useful, and interviewers may test whether you know how to manipulate data as well as read it.

✅ What You’ll Have by Oct 31

• Strong grasp of SQL query basics
• Confidence with JOINs, GROUP BY, and subqueries
• Ability to insert, update, and delete records safely
• A foundation solid enough to move into functions and reporting in November

November: Functions and Reporting

November is about expanding your SQL toolkit. The weather usually turns gray and chilly this time of year, which makes it a great month to stay indoors and focus on learning. With fewer distractions, you can invest steady time in mastering SQL functions and building your first real reports.

🚀 Course 1: Standard SQL Functions

Spend the first two weeks of November on this course. It introduces you to the most common SQL functions and shows you how to apply them in practical scenarios.

What you’ll cover:

• Text functions: CONCAT, SUBSTRING, REPLACE, UPPER, LOWER
• Numeric functions: ROUND, FLOOR, CAST, modulo, arithmetic expressions
• Date and time functions: EXTRACT, intervals, formatting timestamps
• Handling NULL values: COALESCE, NULLIF
• Advanced aggregate functions: COUNT, SUM, AVG, MIN, MAX with edge cases
• CASE WHEN expressions for conditional logic

Suggested pacing:

• Week 1: Text and numeric functions, handling NULLs
• Week 2: Date/time functions, aggregate functions, CASE WHEN

By the end of the course, you’ll be able to write queries like:
 “Classify customers as high-, medium-, or low-value based on their total spend in the last 30 days.”

🎯 Course 2: Creating Basic SQL Reports

In the second half of November, move on to reporting. This course shows you how to combine everything you’ve learned into queries that generate clear, structured outputs — the kind you’ll use in real business settings.

What you’ll cover:

• Summarizing data with aggregates and grouping
• Using CASE WHEN with GROUP BY to classify data
• Multi-level aggregations for categories and subcategories
• Combining multiple metrics (totals, averages, ratios) in a single report
• Comparing groups side by side (e.g. region vs. region, category vs. category)

Suggested pacing:

• Week 3: Summarizing data, classification with CASE WHEN, grouping
• Week 4: Multi-level aggregations, combining multiple metrics, comparing groups

Tip: if the end of the year gets busy, you can move some of the reporting topics into December’s practice month without losing momentum.

✅ What You’ll Have by Nov 30

• Ability to transform and clean text, numbers, and dates with SQL functions
• Confidence in handling NULL values and applying CASE WHEN logic
• Experience writing business-style reports with multiple metrics and comparisons
• A stronger, interview-ready toolkit that builds directly on your October foundations

December: Practice and Consolidate

December is always a busy month with holidays, travel, and year-end tasks. That’s why this part of the plan is lighter — the focus is on finishing any remaining lessons from November and getting as much hands-on practice as possible. Even if you only manage short study sessions, you’ll still be making progress.

?? Finish What You Started

If you didn’t get through all of Creating Basic SQL Reports in November, use the first part of December to wrap it up. Make sure you’re comfortable with:

• Multi-level aggregations
• Combining multiple metrics in one query
• Comparing groups side by side

This ensures you’ll start the new year with solid reporting skills in place.

🎯 Practice, Practice, Practice

Once you’ve wrapped up reporting, it’s time to reinforce your knowledge with hands-on work. LearnSQL.com offers many SQL Practice courses that let you drill into specific topics or apply your skills in realistic settings. You don’t need to do them all — pick ones you like or ones you want to strengthen. Here are some excellent options:

Some good choices include:

• SQL Practice Set — 88 interactive exercises covering SELECT, JOINs, GROUP BY, and subqueries. A great all-rounder.
• SQL JOINs — Extra work on different join types and tricky edge cases.
• SQL Subqueries — Focused practice on nested and correlated subqueries.
• Basic SQL Practice: A Store — Larger practice set using a store dataset. Good for applying your skills in a “business” scenario.
• Basic SQL Practice: University — Similar idea, but with a university/students dataset — good for variety.
• Basic SQL Practice: Run Queries — More exercises focused on querying, sharpening your core querying fluency.
• Basic SQL Practice: Blog — Practice with data about blog posts, traffic, comments, etc., useful for trend/time queries.

👉 Pick 2 or 3 courses (or more if you have the time) and tackle a few exercises each day. Even 5 a day adds up to 100+ by month’s end — enough to turn theory into muscle memory you can rely on in interviews.

🎄 Optional Challenge: Advent of Code

Every December, the new Advent of Code challenge is released. It’s a free programming challenge that runs every year from December 1 to 25. Each day, a new puzzle is released. While it’s not SQL-specific, many participants use SQL to solve the puzzles. Try a few of them for fun — it’s a great way to keep your brain engaged during the holiday season.

✅ What You’ll Have by Dec 31

• Finished any remaining November material
• Dozens (or even hundreds) of solved SQL exercises from practice courses
• Greater speed and confidence in writing queries under time pressure
• Proven ability to tackle JOINs, subqueries, and reporting tasks fluently
• A resume-ready SQL skill set you’ve tested through consistent practice

By the time the new year begins, you won’t just say you’re learning SQL — you’ll have practiced enough to show it in a job interview.

Ready for the New Year

If you follow this 90-day study plan, you’ll finish the year with a brand-new skill set and the confidence to showcase it in interviews. Instead of waiting for January to make resolutions, you’ll already be ahead — with SQL as a proven, practical strength on your resume.

And if you want to keep going after December, the best way is with the All Forever SQL Plan. It gives you unlimited access to all LearnSQL.com courses — from the beginner tracks you started here, to advanced practice sets, window functions, optimization, and more. With it, you’ll always have the right next step ready, no matter where your SQL journey takes you.

So as the year wraps up, give yourself the best gift: a future-proof skill you’ll use for years to come.

🎁 Next Step: Don’t stop at December. With the All Forever SQL Plan, you get lifetime access to every LearnSQL.com course — from beginner to advanced. That way, you’ll always know what to learn next.