SQL Course Index
46 topics · follow in order
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Module 1 — Foundations
1
Introduction to SQL
What SQL is and why it matters
📖
2
Database & RDBMS
How data is organised
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3
RDBMS Concepts
How relational databases actually work
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4
SQL Data Types
INT, VARCHAR, DATE and more
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Module 2 — Tables
5
CREATE DATABASE
Setting up your database
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6
CREATE TABLE
Defining columns and types
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7
ALTER TABLE
Adding and changing columns
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8
Constraints
NOT NULL, UNIQUE, PRIMARY KEY
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Module 3 — Writing Data
9
INSERT Statement
Adding rows to a table
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10
UPDATE Statement
Changing existing rows
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11
DELETE Statement
Removing rows
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Module 4 — Reading Data
12
SELECT + WHERE
Fetch exactly what you need
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13
SQL Operators
AND, OR, NOT, BETWEEN, IN, LIKE
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14
ORDER BY Clause
Sorting your results
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15
DISTINCT Keyword
Removing duplicate rows
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16
LIMIT Clause
Controlling how many rows
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17
Date & Time Functions
Working with dates
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18
String Functions
Cleaning and shaping text
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Module 5 — Aggregation
19
Aggregate Functions
COUNT, SUM, AVG, MAX, MIN
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20
GROUP BY Clause
Group rows + use MAX()
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21
HAVING Clause
Filter after grouping
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22
CASE WHEN
Conditional logic in queries
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23
NULL Handling
COALESCE, IS NULL, NULLIF
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Module 6 — Keys
24
Primary Key
Uniquely identifying rows
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25
Foreign Key
Linking tables together
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26
Other Keys
Composite, candidate, alternate
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27
Relationships
One-to-one, one-to-many
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Module 7 — JOINs
28
INNER JOIN
Matching rows from both tables
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29
LEFT JOIN
Keep all left table rows
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30
RIGHT JOIN
Keep all right table rows
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31
FULL JOIN
Keep all rows from both
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32
SELF JOIN
A table joining itself
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Module 8 — Advanced
33
Subqueries
Queries inside queries
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34
UNION & UNION ALL
Combining result sets
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35
Views
Saved virtual tables
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36
Indexes
Making queries faster
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37
Transactions
COMMIT and ROLLBACK
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38
ACID Properties
Database reliability
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39
Normalization
Designing clean tables
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40
SQL vs NoSQL
When to use which
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Module 9 — Advanced SQL
41
Window Functions
RANK, ROW_NUMBER, PARTITION BY
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42
CTEs
WITH clause, readable subqueries
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43
LAG & LEAD
Comparing across rows
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Reference & Practice
44
SQL Cheat Sheet
Quick reference for everything
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45
Practice Problems
Apply everything you've learned
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46
SQL Interview Questions
Top 50 questions explained
▶
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