Question 1

What is Quick Recall?

Accepted Answer

Quick Recall is a free study tool on Let's Data Science with two modes: Interview Recall Cards (490+ concept cards across SQL, Python, Statistics, ML & LLMs) and SQL Recall (33 lessons and 71 interactive SQL exercises). Everything runs in your browser — no signup, no installation.

Question 2

Is Quick Recall free?

Accepted Answer

Yes, completely free. All 490+ recall cards and 100+ SQL exercises are available with no signup, no credit card, and no installation required. SQL queries execute directly in your browser using SQLite WebAssembly.

Question 3

What topics do the recall cards cover?

Accepted Answer

Interview Recall Cards cover 5 data science topics: SQL (queries, joins, aggregations), Python (syntax, data structures, libraries), Statistics (probability, distributions, hypothesis testing), Machine Learning (algorithms, evaluation, feature engineering), and LLMs (transformers, attention, fine-tuning).

Question 4

How does the SQL practice work?

Accepted Answer

SQL Recall runs a real SQLite database in your browser using WebAssembly. You write SQL queries in a Monaco code editor, execute them with Cmd+Enter, and get instant results. The tool covers 11 SQL topics from SELECT basics to advanced window functions, with 33 concept lessons and 71 hands-on exercises.

Question 5

Do I need to install anything?

Accepted Answer

No. Both modes — recall cards and SQL exercises — run entirely in your web browser. The SQL engine uses SQLite WebAssembly, so there is no database to set up and no software to install.