How to learn SQL for free | Roadmap to learning SQL
In this video, you will find complete roadmap on how to learn SQL for Beginners, Intermediate level, Advanced level and for database developers.
You will know how to choose a database and what SQL concepts you need to learn to have basic, intermediate, advanced and developer level knowledge of SQL.
Watch the video here:
Pre-Requisites
Choose your relational database (RDBMS)
Most popular RDBMS are:
Oracle
MySQL
Microsoft SQL Server
PostgreSQL
Checkout DB-Engines to get list of popular databases
Install the database
If using cloud based database/datawarehouse then make sure to setup on your system.
Install the IDE
Mentioned here are the IDE for 4 most popular RDBMS:
Basic SQL
Concepts
What is a Relational Database / RDBMS?
How data is stored in a relational database?
What is a schema wrt to a relational database?
SQL commands
DDL, DML, DCL, TCL, DQL
What are commands under each of these category and what each of these commands actually do?
Data Types
String data type like VARCHAR, TEXT etc
Integer data type like INT, NUMBER etc.
DATE
FLOAT / DECIMAL
BOOLEAN
Also check out IDENTITY column (Auto Increment column)
Constraints
Primary key
Foreign key
Check constraint, Not null constraint, Unique constraint, Default etc.
Normalization in SQL
Different normal forms like 1NF, 2NF, 3NF, BCNF
Operators
Arithmetic operator
Logical operator
Comparison operator
UNION, UNION ALL operator
CASE statement
Simple case statement as well nested case statement.
Important SQL clause
DISTINCT clause
Order by clause
Limit / Top clause
INNER join
How to fetch data from multiple tables.
Learning Resources
Install PostgreSQL database and PgAdmin tool:
Database tutorial
Complete Basic SQL tutorial
W3Schools:
Practice Platforms
StrataScratch (Easy SQL problems)
Master Coding for Data Science
LeetCode (Easy SQL problems)
LeetCode - The World's Leading Online Programming Learning Platform
DataLemur (Easy problems)
DataLemur - Ace the SQL & Data Science Interview
Jobs
Business Analyst
Junior Analyst roles
Software Engineer
Intermediate SQL
Concepts
Group By and Having clause
Aggregate functions
Order of Execution
Sub-Queries
CTE table / WITH clause
All type of Joins
LEFT Join, RIGHT Join, FULL OUTER Join
CROSS Join, SELF Join
In-built functions
String functions like Substring, Position, Coalesce etc.
Date functions like Extract, To_Date etc.
Window functions
Most important are RANK, DENSE_RANK, ROW_NUMBER, LEAD, LAG
Also good to learn FIRST_VALUE, LAST_VALUE, NTH_VALUE, NTILE
Views
Learning Resources
Group By, Having clause
Order of Execution
A Look Into SQL's Order Of Execution
Sub-Queries Tutorial
CTE / WITH clause Tutorial
JOINS Tutorial
Part 1:
Part 2:
Window functions Tutorial
Part 1:
Part 2:
Views Tutorial
In-built functions
String Functions:
PostgreSQL LEFT: Get First N Characters in a String
Oracle String Functions By Examples
MySQL String Functions Overview
Date functions:
SQL Server Date Functions Overview
MySQL Date Functions: Handling Date & Time Data More Effectively
Practice Platforms
StrataScratch (Medium level SQL problems)
Master Coding for Data Science
LeetCode (Medium level SQL problems)
LeetCode - The World's Leading Online Programming Learning Platform
DataLemur (Medium level problems)
DataLemur - Ace the SQL & Data Science Interview
SQL case study from Data with Danny
Jobs
Data Analyst
Data Scientist
Advance SQL
Concepts
Recursive SQL Queries
PIVOT table / CROSSTAB function
Materialized Views
Stored Procedure
User Defined Functions
Learning Resources
Recursive SQL Queries
PIVOT table / CROSSTAB function
Materialized Views
Stored Procedure
User Defined Functions
Learn SQL: User-Defined Functions
Practice Platforms
StrataScratch (Hard level SQL problems)
Master Coding for Data Science
LeetCode (Hard level SQL problems)
LeetCode - The World's Leading Online Programming Learning Platform
DataLemur (Hard level problems)
DataLemur - Ace the SQL & Data Science Interview
SQL case study from Data with Danny
Jobs
Data Engineer
ETL Developers
SQL for Database Developers / SQL Developers
Concepts
Indexes
Triggers
Temporary tables
Dynamic Execution of SQL statements
PL/SQL concepts
Variables
Cursors
Collection types
Loop statements
IF Else statement
Exception Handling
Packages
Performance tuning
Explain plan
Table Statistics
Table Partitioning
DBMS_Profiler
SQL Trace and TKProf
Learning Resources
Indexes
SQL index overview and strategy
Triggers
Temporary tables
Introduction to Temporary Tables in SQL Server
Dynamic Execution of SQL statements
PL/SQL concepts
PL/SQL Tutorial - Master PL/SQL Programming Quickly and Easily
Performance tuning
Explain Plan:
Understanding Oracle Explain Plan
EXPLAIN PLAN FOR and DBMS_XPLAN.DISPLAY
Table Statistics:
Table Partitioning:
DBMS_Profiler:
SQL Trace and TKProf:
SQL trace, 10046, trcsess and tkprof in Oracle
Jobs
Database Developers
SQL Developers
