SQL Learning Roadmap
Level 1: Fundamentals
Master the core building blocks of SQL - from basic queries to data aggregation.
1.1 Basic SQL Syntax
SELECT
Choose specific columns from your data
FROM
Specify which table to query
WHERE
Filter your data with conditions
ORDER BY
Sort your results
AS
Create aliases for columns and tables
LIMIT
Control the number of rows returned
1.2 Data Cleaning
DISTINCT
Remove duplicate values
AND
Combine multiple conditions
OR
At least one condition must be true
NOT
Negate a condition
LIKE
Pattern matching with wildcards
BETWEEN
Filter values within a range
IN
Check if value exists in a list
CASE WHEN
Create conditional logic
COALESCE
Handle NULL values
CAST
Convert data types
1.3 Data Aggregation
SUM
Calculate total values
AVG
Calculate average values
MIN
Find minimum values
MAX
Find maximum values
COUNT
Count rows or non-null values
GROUP BY
Group rows by column values
HAVING
Filter grouped results
Hands-On Practice: Checkpoint 1
Practice Easy Questions
Apply your fundamental SQL knowledge through hands-on practice with easy-level questions to reinforce core concepts
Fundamentals Project
Build a real-world SQL project focused on data cleaning and basic analysis to solidify your foundational skills
Level 2: Table Relationships
Learn to combine data from multiple tables using various types of joins.
2.1 Combining Tables
INNER JOIN
Get matching records from both tables
LEFT JOIN
Get all records from left table
RIGHT JOIN
Get all records from right table
FULL OUTER JOIN
Get all records from both tables
SELF JOIN
Join a table with itself
CROSS JOIN
Create cartesian product
UNION
Combine results from multiple queries
Hands-On Practice: Checkpoint 2
Practice Medium Questions
Challenge yourself with medium-difficulty problems that require combining tables and complex join operations
Joins Project
Create an exploratory data analysis project using multiple joined datasets to practice real-world table relationships
Level 3: Advanced Analytics
Master window functions and complex queries for sophisticated data analysis.
3.1 Window Functions
OVER
Define window for calculations
PARTITION BY
Divide data into partitions
ROWS BETWEEN
Define row-based window frames
RANGE BETWEEN
Define value-based window frames
ROW_NUMBER
Assign unique row numbers
RANK
Rank values with gaps
DENSE_RANK
Rank values without gaps
LAG
Access previous row values
LEAD
Access next row values
FIRST_VALUE / LAST_VALUE
Get boundary values in window
NTILE
Divide data into buckets
PERCENT_RANK
Calculate relative positions
3.2 Subqueries & CTEs
Hands-On Practice: Checkpoint 3
Practice Hard Questions
Master advanced SQL techniques by solving 10 challenging problems that test your window functions and complex query skills
Advanced Analytics Project
Develop a comprehensive SQL project that uncovers deep insights and provides data-driven recommendations using advanced analytical techniques
Level 4: Data Engineering
Learn to create, modify, and manage database structures and data.
4.1 Data Definition
CREATE TABLE
Define new database tables
ALTER TABLE
Modify existing table structure
DROP TABLE
Remove tables from database
PRIMARY KEY
Define unique identifiers
FOREIGN KEY
Create table relationships
UNIQUE
Ensure column uniqueness
4.2 Data Modification
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