Data Scholar

SQL Level 1 : Foundations

Basics of SQL

9 modules83 topics

About this course
This course is designed to make learners comfortable and confident in writing basic to intermediate SQL queries independently. It starts with core querying concepts such as SELECT, filtering, sorting, and aggregations, then progresses to GROUP BY, HAVING, different types of JOINs, subqueries, CASE statements, CTEs, and basic window functions. The course emphasizes hands-on query writing and problem-solving, enabling learners to understand business requirements, translate them into SQL logic, combine data from multiple tables, perform calculations and aggregations, and solve common real-world data analysis problems.
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Curriculum

M10. Database Setup1 topic
·Module overview
  1. 1.1Resources
M21. SQL & Database Fundamentals8 topics
·Module overview
  1. 2.11.1 What is SQL and Why Do We Use It?
  2. 2.21.2 Relational Databases and RDBMS
  3. 2.31.3 Database, Schema, Table, Row and Column
  4. 2.41.4 Primary Keys and Foreign Keys
  5. 2.51.5 Common SQL Data Types
  6. 2.61.6 Understanding a Simple Relational Data Model
  7. 2.71.7 SQL Syntax and Query Structure
  8. 2.81.8 Your First SQL Query
M32. SELECT and Basic Querying8 topics
·Module overview
  1. 3.12.1 SELECT and FROM
  2. 3.22.2 Selecting Multiple Columns
  3. 3.32.3 SELECT * and When to Avoid It
  4. 3.42.4 Column Aliases with AS
  5. 3.52.5 DISTINCT and Removing Duplicate Results
  6. 3.62.6 LIMIT / TOP / FETCH
  7. 3.72.7 Writing Readable SQL Queries
  8. 3.8Exercises
M43. Filtering Data11 topics
·Module overview
  1. 4.13.1 WHERE Clause
  2. 4.23.2 Comparison Operators
  3. 4.33.3 AND, OR and NOT
  4. 4.43.4 Operator Precedence and Parentheses
  5. 4.53.5 BETWEEN
  6. 4.63.6 IN and NOT IN
  7. 4.73.7 LIKE and Pattern Matching
  8. 4.83.8 Working with NULL: IS NULL and IS NOT NULL
  9. 4.93.9 Combining Multiple Filtering Conditions
  10. 4.103.10 Common Filtering Mistakes
  11. 4.11Exercises
M54. Sorting and Transforming Results10 topics
·Module overview
  1. 5.14.1 ORDER BY
  2. 5.24.2 Sorting by Multiple Columns
  3. 5.34.3 ASC and DESC
  4. 5.44.4 Arithmetic Operations in SELECT
  5. 5.54.5 Calculated Columns
  6. 5.64.6 CASE WHEN
  7. 5.74.7 Multiple Conditions with CASE
  8. 5.84.8 COALESCE and Handling NULL Values
  9. 5.94.9 CAST and Data Type Conversion
  10. 5.10Exercises
M65. SQL Functions15 topics
·Module overview
  1. 6.15.1 Introduction to SQL Functions
  2. 6.25.2 Scalar vs Aggregate Functions
  3. 6.35.3 String Functions
  4. 6.45.4 UPPER, LOWER and TRIM
  5. 6.55.5 CONCAT and Combining Strings
  6. 6.65.6 SUBSTRING and String Extraction
  7. 6.75.7 String Length and Replacement Functions
  8. 6.85.8 Date and Time Data
  9. 6.95.9 Current Date and Time Functions
  10. 6.105.10 Extracting Year, Month and Day
  11. 6.115.11 Date Differences and Date Arithmetic
  12. 6.125.12 Numeric Functions
  13. 6.135.13 ROUND, CEILING and FLOOR
  14. 6.14Topic 14
  15. 6.15Exercises
M76. Aggregations12 topics
·Module overview
  1. 7.16.1 What is Aggregation?
  2. 7.26.2 COUNT
  3. 7.36.3 SUM, AVG, MIN and MAX
  4. 7.46.4 COUNT(*) vs COUNT(column) vs COUNT(DISTINCT column)
  5. 7.56.5 GROUP BY
  6. 7.66.6 Grouping by Multiple Columns
  7. 7.76.7 WHERE with Aggregations
  8. 7.86.8 HAVING
  9. 7.96.9 WHERE vs HAVING
  10. 7.106.10 Conditional Aggregation with CASE WHEN
  11. 7.116.11 NULL Behaviour in Aggregate Functions
  12. 7.12Exercises
M87. Joins18 topics
·Module overview
  1. 8.17.1 Why Do We Need Joins?
  2. 8.27.2 Understanding Table Relationships
  3. 8.37.3 One-to-One, One-to-Many and Many-to-Many Relationships
  4. 8.47.4 Join Keys and Join Conditions
  5. 8.57.5 INNER JOIN
  6. 8.67.6 LEFT JOIN
  7. 8.77.7 RIGHT JOIN
  8. 8.87.8 FULL OUTER JOIN
  9. 8.97.9 Joining Multiple Tables
  10. 8.107.10 Joining on Multiple Conditions
  11. 8.117.11 Table Aliases in Joins
  12. 8.127.12 Self Join
  13. 8.137.13 Cross Join
  14. 8.147.14 NULLs in Joins
  15. 8.157.15 Duplicate Rows After Joins
  16. 8.167.16 Join Cardinality and Row Multiplication
  17. 8.177.17 Common Join Mistakes
  18. 8.18Exercises
M9Solutions0 topics
·Module overview